hdu 1572 全排列的搜索

好久没写搜索的题目了 复习一下/。/ 这道题目是暴力的全排列
#include<cstdio>
#include<iostream>
#include<cstring>
#define maxn 31
#define inf 1<<29
using namespace std;
int mapp[maxn][maxn],line[8],minn,vis[8];
int k;
int mymin(int x,int y)
{
    if(x>y) return y;
    else return x;
}
void dfs(int pos,int time,int cost)
{
    if(time>k)
    {
        //cout<<minn<<endl;
        minn=mymin(minn,cost);
        return;
    }
    for(int i=1;i<=k;i++)
    {
        if(vis[i]) continue;
        vis[i]=1;
        //cout<<i<<' '<<time<<endl;
        dfs(i,time+1,cost+mapp[line[pos]][line[i]]);
        vis[i]=0;
    }
}
int main()
{
    int t;
    cin.sync_with_stdio(false);
    while(cin>>t&&t)
    {
        for(int i=0;i<t;i++) for(int j=0;j<t;j++) cin>>mapp[i][j];
        cin>>k;
        for(int i=1;i<=k;i++) cin>>line[i],vis[i]=0;
        minn=inf;
        dfs(0,1,0);
        cout<<minn<<endl;
    }
    return 0;
}