记搜TLE#4#5求调

#include<bits/stdc++.h>
using namespace std;
int n,answ,len[25][25],g[(1<<22)-1][25];
bool vis[25];
void dfs(int ww,int nw,int dep,int ans){
	if(dep==n&&nw==n){
		if(answ==0||answ>ans)answ=ans;
		return;
	}
	for(int i=2;i<=n;i++){
		if(vis[i])continue;
		int bb=ww+(1<<i-1);
		if(g[bb][i]<=ans+len[nw][i]&&g[bb][i])continue;
		g[bb][i]=ans+len[nw][i];
		vis[i]=1;
		dfs(bb,i,dep+1,g[bb][i]);
		vis[i]=0;
	}
}
signed main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			cin>>len[i][j];
		}
	}
	dfs(1,1,1,0);
    printf("%d",answ);
}