最小生成树-PRIM算法

#include<iostream>
#include<cstring>
using namespace std;

typedef char DataType;
#define MAXV 50
#define MAXE 100
#define INFINITY 65535


typedef struct Graph
{
    DataType vexs[MAXV];
    int arc[MAXV][MAXV];
    int VNum,ENum;
}MyGraph;

typedef struct shortEdge
{
    int adjvex;
    int lowcost;

};

void CreatGraph(MyGraph *G);
int MinEdge(MyGraph *G,shortEdge *shortE);
void Prim(MyGraph *G,shortEdge *shortE);

void CreatGraph(MyGraph *G)
{
    int i,j,k,w;
    cout<<"请输入图的顶点数和边数：";
    cin>>G->VNum>>G->ENum;

    cout<<"请输入图的顶点信息：";
    for(i=0;i<G->VNum;i++)
    {
        cin>>G->vexs[i];
    }

    for(i=0;i<G->VNum;i++)
        for(j=0;j<G->ENum;j++)
    {
        G->arc[i][j]=INFINITY;
    }

    for(k=0;k<G->ENum;k++)
    {
        cout<<"请输入边(vi,vj)所依附的边的下标i、j的值以及权值w："<<endl;
        cin>>i>>j>>w;
        G->arc[i][j]=w;
        G->arc[j][i]=w;
    }
}

/*实现在shortE中查找最小权值*/
int MinEdge(MyGraph *G,shortEdge *shortE)
{
    int i;
    int index=-1;
    unsigned int min=INFINITY;
    for(i=0;i<G->ENum;i++)
        {
            if(shortE[i].lowcost<min&&shortE[i].lowcost!=0)
            {
                min=shortE[i].lowcost;
                index=i;
            }
        }
        return index;
}

void Prim(MyGraph *G,shortEdge* shortE)
{
    int i,j,k;
    for(i=1;i<G->ENum;i++)
    {
        shortE[i].lowcost=G->arc[0][i];
        shortE[i].adjvex=0;
    }
    shortE[0].lowcost=0;


    for(i=1;i<G->VNum;i++)
    {
        k=MinEdge(G,shortE);
        cout << G->vexs[shortE[k].adjvex]
             << "→"
             <<G->vexs[k]
             <<"("
             <<shortE[k].lowcost
             <<")"<<endl;

        shortE[k].lowcost=0;
        for(j=1;j<G->VNum;j++)
        if(G->arc[k][j]<shortE[j].lowcost){
            shortE[j].lowcost=G->arc[k][j];
            shortE[j].adjvex=k;
        }
    }
}

int main()
{
    MyGraph *G=new MyGraph;
    shortEdge *SE=new shortEdge;
    CreatGraph(G);
    cout<<"最小生成树(PRIM):"<<endl;
    Prim(G,SE);
}