diff --git a/core/config/main.php b/core/config/main.php
index be7c0cf..2c1e8cb 100755
--- a/core/config/main.php
+++ b/core/config/main.php
@@ -93,5 +93,5 @@
     $g_config['vote']                   = "./tmp/vote/vote.txt";
     $g_config['voteTopics']             = "./tmp/vote/voteTopics.txt_";
     $g_config['use_js_cache']           = true;
-    $g_config['engine_version']         = 80;    
+    $g_config['engine_version']         = 81;    
 ?>
diff --git a/script/features/algorithms/model/plugins/FindShortPatchsFromOne.js b/script/features/algorithms/model/plugins/FindShortPatchsFromOne.js
index e8cc316..97136b9 100644
--- a/script/features/algorithms/model/plugins/FindShortPatchsFromOne.js
+++ b/script/features/algorithms/model/plugins/FindShortPatchsFromOne.js
@@ -211,7 +211,7 @@ FindShortPatchsFromOne.prototype.IsSupportMultiGraph = function()
 
 FindShortPatchsFromOne.prototype.IsSupportNegativeWeight = function()
 {
-    return false;
+    return true;
 }
 
 // Factory for connected components.
diff --git a/script/features/algorithms/model/plugins/ShortestPath.js b/script/features/algorithms/model/plugins/ShortestPath.js
index 83fd97d..00dd8ce 100644
--- a/script/features/algorithms/model/plugins/ShortestPath.js
+++ b/script/features/algorithms/model/plugins/ShortestPath.js
@@ -46,16 +46,28 @@ FindShortPathNew.prototype.result = function(resultCallback)
 {
     if (this.firstObject && this.secondObject)
     {
-        this.outResultCallback = function (result ) { resultCallback(result); };
-        self = this;
-        this.CalculateAlgorithm("dsp", 
-            [
-            {name: "start", value: this.firstObject.id},
-            {name: "finish", value: this.secondObject.id}
-            ], function (pathObjects, properties, results)
-            {
-                self.resultCallback(pathObjects, properties, results);
-        });
+        if (!this.graph.hasNegative())
+        {
+            this.outResultCallback = function (result ) { resultCallback(result); };
+            self = this;
+            this.CalculateAlgorithm("dsp", 
+                [
+                {name: "start", value: this.firstObject.id},
+                {name: "finish", value: this.secondObject.id}
+                ], function (pathObjects, properties, results)
+                {
+                    self.resultCallback(pathObjects, properties, results);
+            });
+        } else {
+            this.outResultCallback = function (result ) { resultCallback(result); };
+            self = this;
+            this.CalculateAlgorithm("blf", [
+                {name: "start", value : this.firstObject.id}   
+                ], function (pathObjects, properties, results)
+                {
+                    self.resultCallbackBellmanFord(pathObjects, properties, results);
+                });
+        }
     }
     return null;
 }
@@ -106,6 +118,104 @@ FindShortPathNew.prototype.resultCallback = function(pathObjects, properties, re
     this.outResultCallback(outputResult);
 }
 
+FindShortPathNew.prototype.resultCallbackBellmanFord = function(pathObjects, properties, results)
+{
+    var outputResult = {};
+    outputResult["version"] = 1;
+    outputResult["minPath"] = true;
+    
+    this.pathObjects = pathObjects;
+    this.properties = properties;
+    
+    var bFound = results.length > 0 && results[0].value < this.infinityValue && (results[0].type == 1 || results[0].type == 2);
+    
+    if (bFound)
+    {
+        this.selectedObjects = {};
+
+        let prevNodeId = -1;
+
+        let currentDistance = 0;
+        let currentSelectedObjects = [];
+        let currentSelectedNodes = [];
+
+        let dataForTargetVertex = {};
+        
+        let pushVertex = function (currentDistance, currentSelectedObjects, currentSelectedNodes) {
+            let targetVertexId = currentSelectedObjects[currentSelectedObjects.length - 1];
+            dataForTargetVertex[targetVertexId] = {distance: currentDistance, objects: currentSelectedObjects, nodes: currentSelectedNodes};
+        }
+        
+        for (var i = 0; i < results.length; i++)
+        {
+          if (results[i].type == 6)
+          {
+            pushVertex(currentDistance, currentSelectedObjects, currentSelectedNodes);
+            currentDistance = 0;
+            prevNodeId = -1;
+            currentSelectedObjects = [];
+            currentSelectedNodes = [];
+          }
+  
+          if (results[i].type == 4)
+          {
+            var nodeId = parseInt(results[i].value);
+            var vertex = this.graph.FindVertex(nodeId);
+            if (prevNodeId >= 0)
+            {
+              var edgeObject = this.graph.FindEdgeMin(prevNodeId, nodeId);
+              currentSelectedObjects.push(edgeObject.id);
+              currentDistance += edgeObject.GetWeight();
+            }
+            prevNodeId = nodeId;
+            currentSelectedObjects.push(nodeId);
+            currentSelectedNodes.push(nodeId);              
+          }
+        }
+        
+        pushVertex(currentDistance, currentSelectedObjects, currentSelectedNodes);
+        
+        let pathObjectsToTarget = dataForTargetVertex[this.secondObject.id].objects;
+        let distanceToTarget    = dataForTargetVertex[this.secondObject.id].distance;
+        let pathNodes = dataForTargetVertex[this.secondObject.id].nodes;
+
+        for (var i = 0; i < pathObjectsToTarget.length; i++)
+        {
+            this.selectedObjects[pathObjectsToTarget[i]] = 1;
+        }
+    
+        this.message = g_shortestPathResult.replace("%d", (distanceToTarget * 1).toString());
+        
+        outputResult["paths"] = [];
+        outputResult["paths"].push(pathNodes);
+        
+        this.message = this.message + ": ";
+        for (var i = 0; i < pathNodes.length; i++)
+        {
+            this.message = this.message + this.graph.FindVertex(pathNodes[i]).mainText + ((i < pathNodes.length - 1) ? "&rArr;" : "");
+        }
+
+        for (let targetId in dataForTargetVertex) 
+        {
+            this.properties[targetId] = {};
+            this.properties[targetId]['lowestDistance'] = dataForTargetVertex[targetId].distance;
+        }
+        
+        this.message = this.message + " <select style=\"float:right\" id=\"enumReport\"></select>";
+        
+        this.updateUpText();
+    }
+    else
+    {
+        this.message = g_pathNotExists;
+    }
+    this.secondObject = null;
+    this.firstObject = null;
+    
+    this.outResultCallback(outputResult);
+}
+
+
 FindShortPathNew.prototype.selectVertex = function(vertex)
 {
 	this.pathObjects = null;
@@ -223,7 +333,7 @@ FindShortPathNew.prototype.IsSupportMultiGraph = function ()
 
 FindShortPathNew.prototype.IsSupportNegativeWeight = function()
 {
-    return false;
+    return true;
 }
 
 
diff --git a/script/features/graphoffline/Graphoffline.Emscripten.wasm b/script/features/graphoffline/Graphoffline.Emscripten.wasm
index 12d16e6..fc6bf70 100644
Binary files a/script/features/graphoffline/Graphoffline.Emscripten.wasm and b/script/features/graphoffline/Graphoffline.Emscripten.wasm differ
diff --git a/script/pages/create_graph_by_edge_list/api/index.js.cache b/script/pages/create_graph_by_edge_list/api/index.js.cache
index 5bccdc0..91330c9 100644
--- a/script/pages/create_graph_by_edge_list/api/index.js.cache
+++ b/script/pages/create_graph_by_edge_list/api/index.js.cache
@@ -1,4 +1,4 @@
-moduleLoader.beginCacheLoading(["/script/entities/graph/api/index.js?v=75","/script/shared/point.js?v=75","/script/entities/edge/api/index.js?v=75","/script/entities/edge/model/BaseEdge.js?v=75","/script/entities/edge/model/EdgeModel.js?v=75","/script/entities/vertex/api/index.js?v=75","/script/entities/vertex/model/BaseVertex.js?v=75","/script/entities/vertex/model/VertexModel.js?v=75","/script/entities/graph/model/Graph.js?v=75",]);{let modulDir="pages/create_graph_by_edge_list/";doInclude([include("entities/graph/api/index.js")]);}
+moduleLoader.beginCacheLoading(["/script/entities/graph/api/index.js?v=77","/script/shared/point.js?v=77","/script/entities/edge/api/index.js?v=77","/script/entities/edge/model/BaseEdge.js?v=77","/script/entities/edge/model/EdgeModel.js?v=77","/script/entities/vertex/api/index.js?v=77","/script/entities/vertex/model/BaseVertex.js?v=77","/script/entities/vertex/model/VertexModel.js?v=77","/script/entities/graph/model/Graph.js?v=77",]);{let modulDir="pages/create_graph_by_edge_list/";doInclude([include("entities/graph/api/index.js")]);}
 {let modulDir="entities/graph/";doInclude([include("shared/point.js"),include("entities/edge/api/index.js"),include("entities/vertex/api/index.js"),include("model/Graph.js",modulDir)])}function Point(x,y){this.x=x||0;this.y=y||0;};Point.prototype.x=null;Point.prototype.y=null;Point.prototype.add=function(v){return new Point(this.x+v.x,this.y+v.y);};Point.prototype.addValue=function(v){return new Point(this.x+v,this.y+v);};Point.prototype.clone=function(){return new Point(this.x,this.y);};Point.prototype.degreesTo=function(v){var dx=this.x-v.x;var dy=this.y-v.y;var angle=Math.atan2(dy,dx);return angle*(180/Math.PI);};Point.prototype.distance=function(v){return Math.sqrt(this.distanceSqr(v));};Point.prototype.distanceSqr=function(v){var x=this.x-v.x;var y=this.y-v.y;return x*x+y*y;};Point.prototype.equals=function(toCompare){return this.x==toCompare.x&&this.y==toCompare.y;};Point.prototype.interpolate=function(v,f){return new Point((this.x+v.x)*f,(this.y+v.y)*f);};Point.prototype.length=function(){return Math.sqrt(this.x*this.x+this.y*this.y);};Point.prototype.normalize=function(thickness){var l=this.length();this.x=this.x/l*thickness;this.y=this.y/l*thickness;return new Point(this.x,this.y);};Point.prototype.normalizeCopy=function(thickness){var l=this.length();return new Point(this.x/l*thickness,this.y/l*thickness);};Point.prototype.orbit=function(origin,arcWidth,arcHeight,degrees){var radians=degrees*(Math.PI/180);this.x=origin.x+arcWidth*Math.cos(radians);this.y=origin.y+arcHeight*Math.sin(radians);};Point.prototype.rotate=function(center,degrees){var radians=degrees*(Math.PI/180);offset=this.subtract(center);this.x=offset.x*Math.cos(radians)-offset.y*Math.sin(radians);this.y=offset.x*Math.sin(radians)+offset.y*Math.cos(radians);this.x=this.x+center.x;this.y=this.y+center.y;return this;};Point.prototype.offset=function(dx,dy){this.x+=dx;this.y+=dy;};Point.prototype.subtract=function(v){return new Point(this.x-v.x,this.y-v.y);};Point.prototype.subtractValue=function(value){return new Point(this.x-value,this.y-value);};Point.prototype.multiply=function(value){return new Point(this.x*value,this.y*value);};Point.prototype.toString=function(){return"(x="+this.x+", y="+this.y+")";};Point.prototype.normal=function(){return new Point(-this.y,this.x);};Point.prototype.min=function(point)
 {return new Point(Math.min(this.x,point.x),Math.min(this.y,point.y));};Point.prototype.max=function(point)
 {return new Point(Math.max(this.x,point.x),Math.max(this.y,point.y));};Point.prototype.inverse=function()
@@ -88,7 +88,7 @@ else
 BaseEdge.prototype.SetWeight=function(weight)
 {var useWeight=false;if(!isNaN(parseInt(weight,10)))
 {useWeight=true;}
-weight=(!isNaN(parseInt(weight,10))&&weight>=0)?weight:1;this.weight=Number(weight);this.useWeight=useWeight;}
+weight=(!isNaN(parseInt(weight,10)))?weight:1;this.weight=Number(weight);this.useWeight=useWeight;}
 BaseEdge.prototype.SetUpText=function(text)
 {this.upText=text;}
 BaseEdge.prototype.resetOwnStyle=function(index)
@@ -216,11 +216,11 @@ BaseVertex.prototype.hasOwnStyleFor=function(index)
 const defaultVertexDiameter=30;function VertexModel()
 {this.diameter=globalApplication.GetDefaultVertexSize();}
 function Graph()
-{this.vertices=[];this.edges=[];this.uidGraph=0;this.uidEdge=10000;this.hasDirect=false;this.isMultiGraph=false;};Graph.prototype.infinity=1E8;Graph.prototype.maxVertices=1000;Graph.prototype.edgesOffset=10000;Graph.prototype.AddNewVertex=function(vertex)
+{this.vertices=[];this.edges=[];this.uidGraph=0;this.uidEdge=10000;this.hasDirect=false;this.isMultiGraph=false;this.hasNegativeWeight=false;};Graph.prototype.infinity=1E8;Graph.prototype.maxVertices=1000;Graph.prototype.edgesOffset=10000;Graph.prototype.AddNewVertex=function(vertex)
 {if(this.vertices.length<=this.maxVertices)
 {vertex.SetId(this.uidGraph);this.uidGraph=this.uidGraph+1;this.vertices.push(vertex);}
 return this.vertices.length-1;}
-Graph.prototype.ClearGraph=function(){this.vertices=[];this.edges=[];this.uidGraph=0;this.uidEdge=10000;this.hasDirect=false;this.isMultiGraph=false;}
+Graph.prototype.ClearGraph=function(){this.vertices=[];this.edges=[];this.uidGraph=0;this.uidEdge=10000;this.hasDirect=false;this.isMultiGraph=false;this.hasNegativeWeight=false;}
 Graph.prototype.AddNewEdgeSafe=function(graph1,graph2,isDirect,weight,replaceIfExists=true)
 {return this.AddNewEdge(new BaseEdge(graph1,graph2,isDirect,weight),replaceIfExists);}
 Graph.prototype.AddNewEdge=function(edge,replaceIfExists)
@@ -232,11 +232,11 @@ else
 {if(edge1!=null&&replaceIfExists)
 this.DeleteEdge(edge1);if(edgeRevert!=null&&!edgeRevert.isDirect&&replaceIfExists)
 this.DeleteEdge(edgeRevert);this.edges.push(edge);}
-this.isMultiGraph=this.checkMutiGraph();return this.edges.length-1;}
+this.isMultiGraph=this.checkMutiGraph();this.hasNegativeWeight=this.checkNegativeWeight();return this.edges.length-1;}
 Graph.prototype.DeleteEdge=function(edgeObject)
 {var index=this.edges.indexOf(edgeObject);if(index>-1)
 {this.edges.splice(index,1);}
-this.isMultiGraph=this.checkMutiGraph();}
+this.isMultiGraph=this.checkMutiGraph();this.hasNegativeWeight=this.checkNegativeWeight();}
 Graph.prototype.DeleteVertex=function(vertexObject)
 {var index=this.vertices.indexOf(vertexObject);if(index>-1)
 {for(var i=0;i<this.edges.length;i++)
@@ -278,7 +278,7 @@ Graph.prototype.FindEdgeMin=function(id1,id2)
 {res=edge;minWeight=edge.weight;}}}
 return res;}
 Graph.prototype.FindEdgeMax=function(id1,id2)
-{var res=null;var maxWeight=0;for(var i=0;i<this.edges.length;i++)
+{var res=null;var maxWeight=-this.infinity;for(var i=0;i<this.edges.length;i++)
 {var edge=this.edges[i];if((edge.vertex1.id==id1&&edge.vertex2.id==id2)||(!edge.isDirect&&edge.vertex1.id==id2&&edge.vertex2.id==id1))
 {if(edge.weight>maxWeight)
 {res=edge;maxWeight=edge.weight;}}}
@@ -392,7 +392,7 @@ var newVertices=[];var bWeightGraph=false;for(var i=0;i<rows.length;i++)
 {for(var j=0;j<rows.length;j++)
 {if(j>=this.vertices.length)
 {var newPos=this.GetRandomPositionOfVertex(matrix,j,viewportSize);newVertices.push(new BaseVertex(newPos.x,newPos.y,currentEnumVerticesType));this.AddNewVertex(newVertices[newVertices.length-1]);}
-if(cols[i][j]>0)
+if(cols[i][j]!=0)
 {var nEdgeIndex=this.AddNewEdgeSafe(this.vertices[i],this.vertices[j],cols[i][j]!=cols[j][i],cols[i][j],true);this.FixEdgeCurve(nEdgeIndex);if(nEdgeIndex>=0)
 {bWeightGraph=bWeightGraph||this.edges[nEdgeIndex].weight!=1;}}}}
 if(!bWeightGraph)
@@ -402,7 +402,7 @@ for(var i=rows.length;i<Math.max(this.vertices.length,rows.length);i++)
 this.VerticesReposition(viewportSize,newVertices);}}
 Graph.prototype.SetPair=function(pairs,viewportSize,currentEnumVerticesType)
 {if(this.TestPair(pairs))
-{this.ClearGraph();let lines=pairs.split("\n");let regExp=[/^(.+)-(.+)$/g,/^(.+)\>(.+)$/g,/^(.+)<(.+)$/g,/^(.+)-\((\d+|\d+\.?\d+)\)-(.+)$/g,/^(.+)-\((\d+|\d+\.?\d+)\)\>(.+)$/g,/^(.+)<\((\d+|\d+\.?\d+)\)\-(.+)$/g,];let bWeightGraph=false;var newVertices=[];for(var i=0;i<lines.length;i++)
+{this.ClearGraph();let lines=pairs.split("\n");let regExp=[/^(.+)-(.+)$/g,/^(.+)\>(.+)$/g,/^(.+)<(.+)$/g,/^(.+)-\((-?\d+|-?\d+\.?\d+)\)-(.+)$/g,/^(.+)-\((-?\d+|-?\d+\.?\d+)\)\>(.+)$/g,/^(.+)<\((-?\d+|-?\d+\.?\d+)\)\-(.+)$/g,];let bWeightGraph=false;var newVertices=[];for(var i=0;i<lines.length;i++)
 {let line=lines[i];if(line==""){continue;}
 for(let j=regExp.length-1;j>=0;--j){if(!line.match(regExp[j])){continue;}
 let groupes=Array.from(line.matchAll(regExp[j]));let groupe=groupes[0];let vetext1Title=groupe[1];let vertex1=this.FindVertexByTitle(vetext1Title);if(vertex1==null){let newPosition=this.GetRandomPosition(viewportSize);vertex1=this.vertices[this.AddNewVertex(new BaseVertex(newPosition.x,newPosition.y,currentEnumVerticesType))];vertex1.mainText=vetext1Title;newVertices.push(vertex1);}
@@ -509,7 +509,7 @@ Graph.prototype.LoadFromXML=function(xmlText,additionalData)
 this.uidGraph=loadedGraphId;this.uidEdge=loadedEdgeId;$nodes=$xml.find("node");var vertices=[];$nodes.each(function(){var vertex=new BaseVertex();vertex.LoadFromXML($(this));vertices.push(vertex);});this.vertices=vertices;$edges=$xml.find("edge");var edges=[];var graph=this;$edges.each(function(){var edge=new BaseEdge();edge.LoadFromXML($(this),graph);if(edge.id<graph.uidEdge){edge.id=graph.uidEdge;graph.uidEdge++;}
 edges.push(edge);});this.edges=edges;$additional=$xml.find("additional");if($additional.length!=0&&additionalData!=null)
 {additionalData["data"]=$additional.attr('data');}
-this.isMultiGraph=this.checkMutiGraph();}
+this.isMultiGraph=this.checkMutiGraph();this.hasNegativeWeight=this.checkNegativeWeight();}
 Graph.prototype.hasDirectEdge=function()
 {var res=false;for(var i=0;i<this.edges.length;i++)
 {if(this.edges[i].isDirect)
@@ -552,8 +552,14 @@ start[edge.vertex1.id]=edge.vertex2.id;if(!edge.isDirect)
 {res=true;break;}
 start[edge.vertex2.id]=edge.vertex1.id;}}
 return res;}
+Graph.prototype.checkNegativeWeight=function()
+{var res=false;for(var i=0;i<this.edges.length&&!res;i++)
+{var edge=this.edges[i];res=edge.GetWeight()<0;}
+return res;}
 Graph.prototype.isMulti=function()
 {return this.isMultiGraph;}
+Graph.prototype.hasNegative=function()
+{return this.hasNegativeWeight;}
 Graph.prototype.isNeedReposition=function()
 {var res=false;for(var i=0;i<this.vertices.length;i++)
 {res=res||this.vertices[i].IsUndefinedPosition();}
diff --git a/script/pages/create_graph_by_incidence_matrix/api/index.js.cache b/script/pages/create_graph_by_incidence_matrix/api/index.js.cache
index cddc036..4d351e4 100644
--- a/script/pages/create_graph_by_incidence_matrix/api/index.js.cache
+++ b/script/pages/create_graph_by_incidence_matrix/api/index.js.cache
@@ -1,4 +1,4 @@
-moduleLoader.beginCacheLoading(["/script/entities/graph/api/index.js?v=75","/script/shared/point.js?v=75","/script/entities/edge/api/index.js?v=75","/script/entities/edge/model/BaseEdge.js?v=75","/script/entities/edge/model/EdgeModel.js?v=75","/script/entities/vertex/api/index.js?v=75","/script/entities/vertex/model/BaseVertex.js?v=75","/script/entities/vertex/model/VertexModel.js?v=75","/script/entities/graph/model/Graph.js?v=75",]);{let modulDir="pages/create_graph_by_matrix/";doInclude([include("entities/graph/api/index.js")]);}
+moduleLoader.beginCacheLoading(["/script/entities/graph/api/index.js?v=77","/script/shared/point.js?v=77","/script/entities/edge/api/index.js?v=77","/script/entities/edge/model/BaseEdge.js?v=77","/script/entities/edge/model/EdgeModel.js?v=77","/script/entities/vertex/api/index.js?v=77","/script/entities/vertex/model/BaseVertex.js?v=77","/script/entities/vertex/model/VertexModel.js?v=77","/script/entities/graph/model/Graph.js?v=77",]);{let modulDir="pages/create_graph_by_matrix/";doInclude([include("entities/graph/api/index.js")]);}
 {let modulDir="entities/graph/";doInclude([include("shared/point.js"),include("entities/edge/api/index.js"),include("entities/vertex/api/index.js"),include("model/Graph.js",modulDir)])}function Point(x,y){this.x=x||0;this.y=y||0;};Point.prototype.x=null;Point.prototype.y=null;Point.prototype.add=function(v){return new Point(this.x+v.x,this.y+v.y);};Point.prototype.addValue=function(v){return new Point(this.x+v,this.y+v);};Point.prototype.clone=function(){return new Point(this.x,this.y);};Point.prototype.degreesTo=function(v){var dx=this.x-v.x;var dy=this.y-v.y;var angle=Math.atan2(dy,dx);return angle*(180/Math.PI);};Point.prototype.distance=function(v){return Math.sqrt(this.distanceSqr(v));};Point.prototype.distanceSqr=function(v){var x=this.x-v.x;var y=this.y-v.y;return x*x+y*y;};Point.prototype.equals=function(toCompare){return this.x==toCompare.x&&this.y==toCompare.y;};Point.prototype.interpolate=function(v,f){return new Point((this.x+v.x)*f,(this.y+v.y)*f);};Point.prototype.length=function(){return Math.sqrt(this.x*this.x+this.y*this.y);};Point.prototype.normalize=function(thickness){var l=this.length();this.x=this.x/l*thickness;this.y=this.y/l*thickness;return new Point(this.x,this.y);};Point.prototype.normalizeCopy=function(thickness){var l=this.length();return new Point(this.x/l*thickness,this.y/l*thickness);};Point.prototype.orbit=function(origin,arcWidth,arcHeight,degrees){var radians=degrees*(Math.PI/180);this.x=origin.x+arcWidth*Math.cos(radians);this.y=origin.y+arcHeight*Math.sin(radians);};Point.prototype.rotate=function(center,degrees){var radians=degrees*(Math.PI/180);offset=this.subtract(center);this.x=offset.x*Math.cos(radians)-offset.y*Math.sin(radians);this.y=offset.x*Math.sin(radians)+offset.y*Math.cos(radians);this.x=this.x+center.x;this.y=this.y+center.y;return this;};Point.prototype.offset=function(dx,dy){this.x+=dx;this.y+=dy;};Point.prototype.subtract=function(v){return new Point(this.x-v.x,this.y-v.y);};Point.prototype.subtractValue=function(value){return new Point(this.x-value,this.y-value);};Point.prototype.multiply=function(value){return new Point(this.x*value,this.y*value);};Point.prototype.toString=function(){return"(x="+this.x+", y="+this.y+")";};Point.prototype.normal=function(){return new Point(-this.y,this.x);};Point.prototype.min=function(point)
 {return new Point(Math.min(this.x,point.x),Math.min(this.y,point.y));};Point.prototype.max=function(point)
 {return new Point(Math.max(this.x,point.x),Math.max(this.y,point.y));};Point.prototype.inverse=function()
@@ -88,7 +88,7 @@ else
 BaseEdge.prototype.SetWeight=function(weight)
 {var useWeight=false;if(!isNaN(parseInt(weight,10)))
 {useWeight=true;}
-weight=(!isNaN(parseInt(weight,10))&&weight>=0)?weight:1;this.weight=Number(weight);this.useWeight=useWeight;}
+weight=(!isNaN(parseInt(weight,10)))?weight:1;this.weight=Number(weight);this.useWeight=useWeight;}
 BaseEdge.prototype.SetUpText=function(text)
 {this.upText=text;}
 BaseEdge.prototype.resetOwnStyle=function(index)
@@ -216,11 +216,11 @@ BaseVertex.prototype.hasOwnStyleFor=function(index)
 const defaultVertexDiameter=30;function VertexModel()
 {this.diameter=globalApplication.GetDefaultVertexSize();}
 function Graph()
-{this.vertices=[];this.edges=[];this.uidGraph=0;this.uidEdge=10000;this.hasDirect=false;this.isMultiGraph=false;};Graph.prototype.infinity=1E8;Graph.prototype.maxVertices=1000;Graph.prototype.edgesOffset=10000;Graph.prototype.AddNewVertex=function(vertex)
+{this.vertices=[];this.edges=[];this.uidGraph=0;this.uidEdge=10000;this.hasDirect=false;this.isMultiGraph=false;this.hasNegativeWeight=false;};Graph.prototype.infinity=1E8;Graph.prototype.maxVertices=1000;Graph.prototype.edgesOffset=10000;Graph.prototype.AddNewVertex=function(vertex)
 {if(this.vertices.length<=this.maxVertices)
 {vertex.SetId(this.uidGraph);this.uidGraph=this.uidGraph+1;this.vertices.push(vertex);}
 return this.vertices.length-1;}
-Graph.prototype.ClearGraph=function(){this.vertices=[];this.edges=[];this.uidGraph=0;this.uidEdge=10000;this.hasDirect=false;this.isMultiGraph=false;}
+Graph.prototype.ClearGraph=function(){this.vertices=[];this.edges=[];this.uidGraph=0;this.uidEdge=10000;this.hasDirect=false;this.isMultiGraph=false;this.hasNegativeWeight=false;}
 Graph.prototype.AddNewEdgeSafe=function(graph1,graph2,isDirect,weight,replaceIfExists=true)
 {return this.AddNewEdge(new BaseEdge(graph1,graph2,isDirect,weight),replaceIfExists);}
 Graph.prototype.AddNewEdge=function(edge,replaceIfExists)
@@ -232,11 +232,11 @@ else
 {if(edge1!=null&&replaceIfExists)
 this.DeleteEdge(edge1);if(edgeRevert!=null&&!edgeRevert.isDirect&&replaceIfExists)
 this.DeleteEdge(edgeRevert);this.edges.push(edge);}
-this.isMultiGraph=this.checkMutiGraph();return this.edges.length-1;}
+this.isMultiGraph=this.checkMutiGraph();this.hasNegativeWeight=this.checkNegativeWeight();return this.edges.length-1;}
 Graph.prototype.DeleteEdge=function(edgeObject)
 {var index=this.edges.indexOf(edgeObject);if(index>-1)
 {this.edges.splice(index,1);}
-this.isMultiGraph=this.checkMutiGraph();}
+this.isMultiGraph=this.checkMutiGraph();this.hasNegativeWeight=this.checkNegativeWeight();}
 Graph.prototype.DeleteVertex=function(vertexObject)
 {var index=this.vertices.indexOf(vertexObject);if(index>-1)
 {for(var i=0;i<this.edges.length;i++)
@@ -278,7 +278,7 @@ Graph.prototype.FindEdgeMin=function(id1,id2)
 {res=edge;minWeight=edge.weight;}}}
 return res;}
 Graph.prototype.FindEdgeMax=function(id1,id2)
-{var res=null;var maxWeight=0;for(var i=0;i<this.edges.length;i++)
+{var res=null;var maxWeight=-this.infinity;for(var i=0;i<this.edges.length;i++)
 {var edge=this.edges[i];if((edge.vertex1.id==id1&&edge.vertex2.id==id2)||(!edge.isDirect&&edge.vertex1.id==id2&&edge.vertex2.id==id1))
 {if(edge.weight>maxWeight)
 {res=edge;maxWeight=edge.weight;}}}
@@ -392,7 +392,7 @@ var newVertices=[];var bWeightGraph=false;for(var i=0;i<rows.length;i++)
 {for(var j=0;j<rows.length;j++)
 {if(j>=this.vertices.length)
 {var newPos=this.GetRandomPositionOfVertex(matrix,j,viewportSize);newVertices.push(new BaseVertex(newPos.x,newPos.y,currentEnumVerticesType));this.AddNewVertex(newVertices[newVertices.length-1]);}
-if(cols[i][j]>0)
+if(cols[i][j]!=0)
 {var nEdgeIndex=this.AddNewEdgeSafe(this.vertices[i],this.vertices[j],cols[i][j]!=cols[j][i],cols[i][j],true);this.FixEdgeCurve(nEdgeIndex);if(nEdgeIndex>=0)
 {bWeightGraph=bWeightGraph||this.edges[nEdgeIndex].weight!=1;}}}}
 if(!bWeightGraph)
@@ -402,7 +402,7 @@ for(var i=rows.length;i<Math.max(this.vertices.length,rows.length);i++)
 this.VerticesReposition(viewportSize,newVertices);}}
 Graph.prototype.SetPair=function(pairs,viewportSize,currentEnumVerticesType)
 {if(this.TestPair(pairs))
-{this.ClearGraph();let lines=pairs.split("\n");let regExp=[/^(.+)-(.+)$/g,/^(.+)\>(.+)$/g,/^(.+)<(.+)$/g,/^(.+)-\((\d+|\d+\.?\d+)\)-(.+)$/g,/^(.+)-\((\d+|\d+\.?\d+)\)\>(.+)$/g,/^(.+)<\((\d+|\d+\.?\d+)\)\-(.+)$/g,];let bWeightGraph=false;var newVertices=[];for(var i=0;i<lines.length;i++)
+{this.ClearGraph();let lines=pairs.split("\n");let regExp=[/^(.+)-(.+)$/g,/^(.+)\>(.+)$/g,/^(.+)<(.+)$/g,/^(.+)-\((-?\d+|-?\d+\.?\d+)\)-(.+)$/g,/^(.+)-\((-?\d+|-?\d+\.?\d+)\)\>(.+)$/g,/^(.+)<\((-?\d+|-?\d+\.?\d+)\)\-(.+)$/g,];let bWeightGraph=false;var newVertices=[];for(var i=0;i<lines.length;i++)
 {let line=lines[i];if(line==""){continue;}
 for(let j=regExp.length-1;j>=0;--j){if(!line.match(regExp[j])){continue;}
 let groupes=Array.from(line.matchAll(regExp[j]));let groupe=groupes[0];let vetext1Title=groupe[1];let vertex1=this.FindVertexByTitle(vetext1Title);if(vertex1==null){let newPosition=this.GetRandomPosition(viewportSize);vertex1=this.vertices[this.AddNewVertex(new BaseVertex(newPosition.x,newPosition.y,currentEnumVerticesType))];vertex1.mainText=vetext1Title;newVertices.push(vertex1);}
@@ -509,7 +509,7 @@ Graph.prototype.LoadFromXML=function(xmlText,additionalData)
 this.uidGraph=loadedGraphId;this.uidEdge=loadedEdgeId;$nodes=$xml.find("node");var vertices=[];$nodes.each(function(){var vertex=new BaseVertex();vertex.LoadFromXML($(this));vertices.push(vertex);});this.vertices=vertices;$edges=$xml.find("edge");var edges=[];var graph=this;$edges.each(function(){var edge=new BaseEdge();edge.LoadFromXML($(this),graph);if(edge.id<graph.uidEdge){edge.id=graph.uidEdge;graph.uidEdge++;}
 edges.push(edge);});this.edges=edges;$additional=$xml.find("additional");if($additional.length!=0&&additionalData!=null)
 {additionalData["data"]=$additional.attr('data');}
-this.isMultiGraph=this.checkMutiGraph();}
+this.isMultiGraph=this.checkMutiGraph();this.hasNegativeWeight=this.checkNegativeWeight();}
 Graph.prototype.hasDirectEdge=function()
 {var res=false;for(var i=0;i<this.edges.length;i++)
 {if(this.edges[i].isDirect)
@@ -552,8 +552,14 @@ start[edge.vertex1.id]=edge.vertex2.id;if(!edge.isDirect)
 {res=true;break;}
 start[edge.vertex2.id]=edge.vertex1.id;}}
 return res;}
+Graph.prototype.checkNegativeWeight=function()
+{var res=false;for(var i=0;i<this.edges.length&&!res;i++)
+{var edge=this.edges[i];res=edge.GetWeight()<0;}
+return res;}
 Graph.prototype.isMulti=function()
 {return this.isMultiGraph;}
+Graph.prototype.hasNegative=function()
+{return this.hasNegativeWeight;}
 Graph.prototype.isNeedReposition=function()
 {var res=false;for(var i=0;i<this.vertices.length;i++)
 {res=res||this.vertices[i].IsUndefinedPosition();}
diff --git a/script/pages/create_graph_by_matrix/api/index.js.cache b/script/pages/create_graph_by_matrix/api/index.js.cache
index 2e3a8c4..98a1c1e 100644
--- a/script/pages/create_graph_by_matrix/api/index.js.cache
+++ b/script/pages/create_graph_by_matrix/api/index.js.cache
@@ -1,4 +1,4 @@
-moduleLoader.beginCacheLoading(["/script/entities/graph/api/index.js?v=75","/script/shared/point.js?v=75","/script/entities/edge/api/index.js?v=75","/script/entities/edge/model/BaseEdge.js?v=75","/script/entities/edge/model/EdgeModel.js?v=75","/script/entities/vertex/api/index.js?v=75","/script/entities/vertex/model/BaseVertex.js?v=75","/script/entities/vertex/model/VertexModel.js?v=75","/script/entities/graph/model/Graph.js?v=75","/script/pages/create_graph_by_matrix/model/createByMatrixMain.js?v=75","/script/pages/create_graph_by_matrix/model/main.js?v=75",]);{let modulDir="pages/create_graph_by_matrix/";doInclude([include("entities/graph/api/index.js"),include("model/createByMatrixMain.js",modulDir),include("model/main.js",modulDir)]);}
+moduleLoader.beginCacheLoading(["/script/entities/graph/api/index.js?v=77","/script/shared/point.js?v=77","/script/entities/edge/api/index.js?v=77","/script/entities/edge/model/BaseEdge.js?v=77","/script/entities/edge/model/EdgeModel.js?v=77","/script/entities/vertex/api/index.js?v=77","/script/entities/vertex/model/BaseVertex.js?v=77","/script/entities/vertex/model/VertexModel.js?v=77","/script/entities/graph/model/Graph.js?v=77","/script/pages/create_graph_by_matrix/model/createByMatrixMain.js?v=77","/script/pages/create_graph_by_matrix/model/main.js?v=77",]);{let modulDir="pages/create_graph_by_matrix/";doInclude([include("entities/graph/api/index.js"),include("model/createByMatrixMain.js",modulDir),include("model/main.js",modulDir)]);}
 {let modulDir="entities/graph/";doInclude([include("shared/point.js"),include("entities/edge/api/index.js"),include("entities/vertex/api/index.js"),include("model/Graph.js",modulDir)])}function Point(x,y){this.x=x||0;this.y=y||0;};Point.prototype.x=null;Point.prototype.y=null;Point.prototype.add=function(v){return new Point(this.x+v.x,this.y+v.y);};Point.prototype.addValue=function(v){return new Point(this.x+v,this.y+v);};Point.prototype.clone=function(){return new Point(this.x,this.y);};Point.prototype.degreesTo=function(v){var dx=this.x-v.x;var dy=this.y-v.y;var angle=Math.atan2(dy,dx);return angle*(180/Math.PI);};Point.prototype.distance=function(v){return Math.sqrt(this.distanceSqr(v));};Point.prototype.distanceSqr=function(v){var x=this.x-v.x;var y=this.y-v.y;return x*x+y*y;};Point.prototype.equals=function(toCompare){return this.x==toCompare.x&&this.y==toCompare.y;};Point.prototype.interpolate=function(v,f){return new Point((this.x+v.x)*f,(this.y+v.y)*f);};Point.prototype.length=function(){return Math.sqrt(this.x*this.x+this.y*this.y);};Point.prototype.normalize=function(thickness){var l=this.length();this.x=this.x/l*thickness;this.y=this.y/l*thickness;return new Point(this.x,this.y);};Point.prototype.normalizeCopy=function(thickness){var l=this.length();return new Point(this.x/l*thickness,this.y/l*thickness);};Point.prototype.orbit=function(origin,arcWidth,arcHeight,degrees){var radians=degrees*(Math.PI/180);this.x=origin.x+arcWidth*Math.cos(radians);this.y=origin.y+arcHeight*Math.sin(radians);};Point.prototype.rotate=function(center,degrees){var radians=degrees*(Math.PI/180);offset=this.subtract(center);this.x=offset.x*Math.cos(radians)-offset.y*Math.sin(radians);this.y=offset.x*Math.sin(radians)+offset.y*Math.cos(radians);this.x=this.x+center.x;this.y=this.y+center.y;return this;};Point.prototype.offset=function(dx,dy){this.x+=dx;this.y+=dy;};Point.prototype.subtract=function(v){return new Point(this.x-v.x,this.y-v.y);};Point.prototype.subtractValue=function(value){return new Point(this.x-value,this.y-value);};Point.prototype.multiply=function(value){return new Point(this.x*value,this.y*value);};Point.prototype.toString=function(){return"(x="+this.x+", y="+this.y+")";};Point.prototype.normal=function(){return new Point(-this.y,this.x);};Point.prototype.min=function(point)
 {return new Point(Math.min(this.x,point.x),Math.min(this.y,point.y));};Point.prototype.max=function(point)
 {return new Point(Math.max(this.x,point.x),Math.max(this.y,point.y));};Point.prototype.inverse=function()
@@ -278,7 +278,7 @@ Graph.prototype.FindEdgeMin=function(id1,id2)
 {res=edge;minWeight=edge.weight;}}}
 return res;}
 Graph.prototype.FindEdgeMax=function(id1,id2)
-{var res=null;var maxWeight=0;for(var i=0;i<this.edges.length;i++)
+{var res=null;var maxWeight=-this.infinity;for(var i=0;i<this.edges.length;i++)
 {var edge=this.edges[i];if((edge.vertex1.id==id1&&edge.vertex2.id==id2)||(!edge.isDirect&&edge.vertex1.id==id2&&edge.vertex2.id==id1))
 {if(edge.weight>maxWeight)
 {res=edge;maxWeight=edge.weight;}}}
diff --git a/script/pages/editor/api/index.js.cache b/script/pages/editor/api/index.js.cache
index 43fa614..73dc55a 100644
--- a/script/pages/editor/api/index.js.cache
+++ b/script/pages/editor/api/index.js.cache
@@ -1,4 +1,4 @@
-moduleLoader.beginCacheLoading(["/script/shared/utils.js?v=76","/script/entities/graph/api/index.js?v=76","/script/shared/point.js?v=76","/script/entities/edge/api/index.js?v=76","/script/entities/edge/model/BaseEdge.js?v=76","/script/entities/edge/model/EdgeModel.js?v=76","/script/entities/vertex/api/index.js?v=76","/script/entities/vertex/model/BaseVertex.js?v=76","/script/entities/vertex/model/VertexModel.js?v=76","/script/entities/graph/model/Graph.js?v=76","/script/features/draw_graph/api/index.js?v=76","/script/features/draw_graph/model/BaseBackgroundDrawer.js?v=76","/script/features/draw_graph/model/BaseEdgeDrawer.js?v=76","/script/features/draw_graph/model/BaseVertexDrawer.js?v=76","/script/features/algorithms/api/index.js?v=76","/script/features/algorithms/model/Algorithms.js?v=76","/script/features/algorithms/model/BaseTraversal.js?v=76","/script/features/base_handler/index.js?v=76","/script/features/default_handler/index.js?v=76","/script/features/add_vertices_handler/index.js?v=76","/script/features/connect_vertices_handler/index.js?v=76","/script/features/delete_objects_handler/index.js?v=76","/script/features/algorithm_handler/index.js?v=76","/script/features/serialization/api/index.js?v=76","/script/features/serialization/model/GraphMLCreator.js?v=76","/script/features/enum_vertices/EnumVertices.js?v=76","/script/pages/editor/model/texts.js?v=76","/script/pages/editor/model/UndoStack.js?v=76","/script/pages/editor/model/DiskSaveLoad.js?v=76","/script/pages/editor/model/Application.js?v=76","/script/pages/editor/ui/ya_metrika.js?v=76","/script/pages/editor/ui/editor.js?v=76","/script/pages/editor/ui/main.js?v=76",]);{function onloadEditor(){console.log("onload() call");doIncludeAsync([include("shared/canvas2svg.js"),include("features/group_rename_handler/index.js"),include("features/saved_graph_handler/index.js"),include("features/saved_graph_image_handler/index.js"),include("features/show_adjacency_matrix/index.js"),include("features/show_distance_matrix/index.js"),include("features/show_incidence_matrix/index.js"),include("features/setup_background_style/index.js"),include("features/setup_edge_style/index.js"),include("features/setup_vertex_style/index.js"),]);postLoadPage();}
+moduleLoader.beginCacheLoading(["/script/shared/utils.js?v=77","/script/entities/graph/api/index.js?v=77","/script/shared/point.js?v=77","/script/entities/edge/api/index.js?v=77","/script/entities/edge/model/BaseEdge.js?v=77","/script/entities/edge/model/EdgeModel.js?v=77","/script/entities/vertex/api/index.js?v=77","/script/entities/vertex/model/BaseVertex.js?v=77","/script/entities/vertex/model/VertexModel.js?v=77","/script/entities/graph/model/Graph.js?v=77","/script/features/draw_graph/api/index.js?v=77","/script/features/draw_graph/model/BaseBackgroundDrawer.js?v=77","/script/features/draw_graph/model/BaseEdgeDrawer.js?v=77","/script/features/draw_graph/model/BaseVertexDrawer.js?v=77","/script/features/algorithms/api/index.js?v=77","/script/features/algorithms/model/Algorithms.js?v=77","/script/features/algorithms/model/BaseTraversal.js?v=77","/script/features/base_handler/index.js?v=77","/script/features/default_handler/index.js?v=77","/script/features/add_vertices_handler/index.js?v=77","/script/features/connect_vertices_handler/index.js?v=77","/script/features/delete_objects_handler/index.js?v=77","/script/features/algorithm_handler/index.js?v=77","/script/features/serialization/api/index.js?v=77","/script/features/serialization/model/GraphMLCreator.js?v=77","/script/features/enum_vertices/EnumVertices.js?v=77","/script/pages/editor/model/texts.js?v=77","/script/pages/editor/model/UndoStack.js?v=77","/script/pages/editor/model/DiskSaveLoad.js?v=77","/script/pages/editor/model/Application.js?v=77","/script/pages/editor/ui/ya_metrika.js?v=77","/script/pages/editor/ui/editor.js?v=77","/script/pages/editor/ui/main.js?v=77",]);{function onloadEditor(){console.log("onload() call");doIncludeAsync([include("shared/canvas2svg.js"),include("features/group_rename_handler/index.js"),include("features/saved_graph_handler/index.js"),include("features/saved_graph_image_handler/index.js"),include("features/show_adjacency_matrix/index.js"),include("features/show_distance_matrix/index.js"),include("features/show_incidence_matrix/index.js"),include("features/setup_background_style/index.js"),include("features/setup_edge_style/index.js"),include("features/setup_vertex_style/index.js"),]);postLoadPage();}
 let modulDir="pages/editor/";doInclude([include("shared/utils.js"),include("entities/graph/api/index.js"),include("features/draw_graph/api/index.js"),include("features/algorithms/api/index.js"),include("features/base_handler/index.js"),include("features/default_handler/index.js"),include("features/add_vertices_handler/index.js"),include("features/connect_vertices_handler/index.js"),include("features/delete_objects_handler/index.js"),include("features/algorithm_handler/index.js"),include("features/serialization/api/index.js"),include("features/enum_vertices/EnumVertices.js"),include("model/texts.js",modulDir),include("model/UndoStack.js",modulDir),include("model/DiskSaveLoad.js",modulDir),include("model/Application.js",modulDir),include("ui/ya_metrika.js",modulDir),include("ui/editor.js",modulDir),include("ui/main.js",modulDir)],onloadEditor);}
 function gEncodeToHTML(str)
 {if(typeof str!=='string')
diff --git a/script/shared/loader.js b/script/shared/loader.js
index 973d7e8..b880114 100644
--- a/script/shared/loader.js
+++ b/script/shared/loader.js
@@ -1,5 +1,5 @@
 // Global version needs to force reload scripts from server.
-let globalVersion = 76;
+let globalVersion = 77;
 
 var include = function(filename, localDir) {
     return {filename: filename, localDir: localDir};