1345：【例4-6】香甜的黄油

香甜的黄油

#include<iostream>
#include<cstring>
#include<cmath>
#define M 0x3f3f3f3f
using namespace std;

const int N=805;
int mapp[N][N],P[N];

int main(){
    int n,p,c;
    cin>>n>>p>>c;
    int x,y,z;
    while(n--){
        scanf("%d",&x);
        P[x]++;
    }
    memset(mapp,M,sizeof(mapp));
    for(int i=0;i<c;i++){
        scanf("%d%d%d",&x,&y,&z);
        mapp[x][y]=mapp[y][x]=z;
    }
    //Floyd
    for(int k=1;k<=p;k++)
        for(int i=1;i<=p;i++)
            for(int j=1;j<=p;j++)
                mapp[i][j]=min(mapp[i][j],mapp[i][k]+mapp[k][j]);
    //枚举每一个点
    int ans=0x7fffffff;
    for(int i=1;i<=p;i++){
        int sum=0;
        for(int j=1;j<=p;j++){
            if(i==j)continue;
            sum+=mapp[j][i]*P[j];
        }
        ans=min(ans,sum);
    }
    cout<<ans;
    return 0;
}