最小生成树之prime算法C/C++

#include <bits/stdc++.h>
using namespace std;
typedef char VertexType;
typedef struct EdgeNode{
   int adjvex;
   int weight;
   struct EdgeNode *nextedge;
}EdgeNode;

typedef struct VNode{
   VertexType data;
   int visited;
   struct EdgeNode *firstedge;
}VNode;

struct ALGraphStruct;
typedef struct ALGraphStruct *ALGraph;
struct ALGraphStruct{
   VNode vexs[1000];
   int vertexnum;
   int edgenum;
};

//创建邻接表
ALGraph CreateALGraph()
{
   ALGraph g=(ALGraph)malloc(sizeof(struct ALGraphStruct));
   g->vertexnum=0;
   g->edgenum=0;
   return g;
}

//查找顶点位置
int Locates(ALGraph g,VertexType v)
{
   for(int i=0;i<g->vertexnum;i++)
       if(g->vexs[i].data==v)
           return i;
   return -1;
}

//增加顶点
void AddVertex(ALGraph g,VertexType v)
{
   int k=Locates(g,v);
   if(k!=-1)
       return ;
   int n=g->vertexnum;
   g->vertexnum++;
   g->vexs[n].data=v;
   g->vexs[n].visited=0;
   g->vexs[n].firstedge=NULL;
}

//查找边
EdgeNode *FindEdge(ALGraph g,int i,int j)
{
   for(EdgeNode *p=g->vexs[i].firstedge;p!=NULL;p=p->nextedge)
       if(p->adjvex==j)
           return p;
   return NULL;
}

//插入边
void InsertEdge(ALGraph g,int i,int j,int w)
{
   EdgeNode *s=(EdgeNode*)malloc(sizeof(struct EdgeNode));
   s->adjvex=i;
   s->weight=w;
   s->nextedge=g->vexs[j].firstedge;
   g->vexs[j].firstedge=s;
}

//增加边
void AddEdge(ALGraph g,VertexType v1,VertexType v2,int w)
{
   EdgeNode *s,*t;
   int i=Locates(g,v1);
   int j=Locates(g,v2);
   if(i==-1 || j==-1)
       return ;
   s=FindEdge(g,i,j);
   if(s!=NULL){
      t=FindEdge(g,j,i);
      if(s->weight>w){
          s->weight=w;
          t->weight=w;
      }
      return;
   }
   InsertEdge(g,i,j,w);
   InsertEdge(g,j,i,w);
   g->edgenum++;
}

//第一个邻接点
int FirstEdge(ALGraph g,int i)
{
   EdgeNode *p=g->vexs[i].firstedge;
   if(p!=NULL)
       return p->adjvex;
   return -1;
}

//下一个邻接点
int NextEdge(ALGraph g,int i,int j)
{
   EdgeNode *p=FindEdge(g,i,j);
   if(p==NULL)
       return -1;
   p=p->nextedge;
   if(p==NULL)
       return -1;
   return p->adjvex;
}

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//邻接表的初始化
void ALGraphInit(ALGraph g)
{
   int n,m,w;
   char v,x,y;
   scanf("%d%d",&n,&m);
   getchar();
   for(int i=0;i<n;i++){
       v=getchar();
       AddVertex(g,v);
   }
   for(int j=0;j<m;j++){
       getchar();
       x=getchar();
       y=getchar();
       w=getchar();
       AddEdge(g,x,y,w);
   }
   for(int k=0;k<n;k++)
       g->vexs[k].visited=1;
}

//最小生成树之prime算法
typedef struct CloseEdge{
int adjvex;
int weight;
}CloseEdge;

int FindMin(CloseEdge closedge[],int n)
{
   int k=-1;
   int min=INT_MAX;
   for(int i=0;i<n;i++){
       if(closedge[i].weight==0)
           continue;
       if(closedge[i].weight<min){
           k=i;
           min=closedge[i].weight;
       }
   }
   return k;
}

int Prime(ALGraph g,ALGraph t,VertexType v)
{
   int lowcost=0;
   int k=Locates(g,v);
   if(k==-1)
       return -1;
   CloseEdge closedge[1000];
   for(int i=0;i<g->vertexnum;i++)
       closedge[i].weight=INT_MAX;
   closedge[k].weight=0;
   AddVertex(t,g->vexs[k].data);
   for(EdgeNode *p=g->vexs[k].firstedge;p!=NULL;p=p->nextedge){
       closedge[p->adjvex].adjvex=k;
       closedge[p->adjvex].weight=p->weight;
   }
   for(int i=0;i<g->vertexnum;i++){
       k=FindMin(closedge,g->vertexnum);
       if(k==-1)
           return -1;
       int j=closedge[k].adjvex;
       AddVertex(t,g->vexs[k].data);
       AddEdge(t,g->vexs[j].data,g->vexs[k].data,closedge[k].weight);
       lowcost+=closedge[k].weight;
       closedge[k].weight=0;
       for(EdgeNode *p=g->vexs[k].firstedge;p!=NULL;p=p->nextedge){
           if(closedge[p->adjvex].weight==0)
               continue;
           if(closedge[p->adjvex].weight>p->weight){
               closedge[p->adjvex].weight=p->weight;
               closedge[p->adjvex].adjvex=k;
           }
       }
   }
   return lowcost;
}

int main()
{
return 0;
}

最小生成树之prime算法C/C++

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