public override MinimumTree miniGeneralTree_Kruskal()
{
int[] vnodeset = new int[NodesCount]; //存放定点联通情况
for (int i = 0; i < vnodeset.Length; i++) //初始化V集合为空
{
vnodeset[i] = i;
}
GraphEdge[] edges = AllEdges;
Sort <GraphEdge> .MergeSort(edges); //对边排序
int edgeidx = 0; //边的索引
int curMiniTreeEdgeCount = 0;
MinimumTree tree = new MinimumTree();
List <GraphEdge> selectededges = new List <GraphEdge>();
while (curMiniTreeEdgeCount < NodesCount - 1)
{
var starnodetidx = _nodes[edges[edgeidx].StartNode.Name];
var Endnodetidx = _nodes[edges[edgeidx].EndNode.Name];
int setidx1 = vnodeset[starnodetidx];
int setidx2 = vnodeset[Endnodetidx];
if (setidx1 != setidx2)
{
selectededges.Add(edges[edgeidx]);
curMiniTreeEdgeCount++;
for (int i = 0; i < NodesCount; i++)
{
if (vnodeset[i] == setidx2)
{
vnodeset[i] = setidx1;
}
}
}
edgeidx++;
}
tree.Add(selectededges);
return(tree);
}
public override MinimumTree miniGeneralTree_Prim(int nodeidx)
{
if (nodeidx < 0 || nodeidx >= NodesCount)
{
return(null);
}
double[] mini_costs = new double[NodesCount]; //到最小生成树最小代价
int[] node_v = new int[NodesCount]; //最小生成树顶点
int[] edge_n = new int[NodesCount]; //最短边
for (int i = 0; i < NodesCount; i++)
{
mini_costs[i] = double.MaxValue; //Max代表不连通
node_v[i] = 0; //0代表当前未放入最小生成树中
edge_n[i] = -1; //当前i节点的最短路径是和谁产生的
}
MinimumTree tree = new MinimumTree();
node_v[nodeidx] = 1; //初始顶点放入最小生成树中
tree.Add(new MinimumTreeNode {
Cost = 0, Name = _nodesarray[nodeidx].Name, ParentName = string.Empty
}, "");
for (int i = 0; i < NodesCount; i++)
{
double cost = getWeight(nodeidx, i);
if (cost >= 0)
{
mini_costs[i] = cost;
edge_n[i] = nodeidx;
}
}
for (int i = 0; i < NodesCount; i++)
{
double minCost = double.MaxValue;
int minIdx = -1;
for (int j = 0; j < NodesCount; j++) //找当前最小节点
{
if (mini_costs[j] < minCost && node_v[j] == 0)
{
minIdx = j;
minCost = mini_costs[j];
}
}
if (minIdx < 0) //没找着，继续
{
continue;
}
node_v[minIdx] = 1; //加入最小生成树
tree.Add(new MinimumTreeNode {
Cost = minCost, Name = _nodesarray[minIdx].Name, ParentName = _nodesarray[edge_n[minIdx]].Name
}, _nodesarray[edge_n[minIdx]].Name);
for (int j = 0; j < NodesCount; j++) //更新当前最小生成树到其他节点的最小代价
{
if (node_v[j] == 0)
{
double cost = getWeight(minIdx, j);
if (cost >= 0 && cost < mini_costs[j]) //更新到最小生成树的代价和边
{
mini_costs[j] = cost;
edge_n[j] = minIdx;
}
}
}
}
return(tree);
}
