HDU 3001

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;
const int inf=1<<30;
struct Edge{
	int u,v,c;
	int next;
}edge[2000];
int tot,n,m;
int head[15];
int dp[60000][11],tir[60000][12],s[12];

struct Status{
	int i,j,c;
	Status(){}
	Status(int ii,int jj,int cc){i=ii,j=jj,c=cc;}
}que[1800000];
int hed,tail;

void addedge(int u,int v,int c){
	edge[tot].u=u;
	edge[tot].v=v;
	edge[tot].c=c;
	edge[tot].next=head[u];
	head[u]=tot++;
}

void init() {  
    s[0]=1;  
    for(int i=1; i<=10; i++)  
        s[i]=s[i-1]*3;  
    for(int i=0; i<=s[10]; i++){  
        int t=i;  
        for(int j=0; j<10; j++){  
            tir[i][j]=t%3;  
            t/=3;  
        }  
    }  
}

void slove(){
	int u,v;
	int ans=inf;
	while(hed<tail){
		Status tmp=que[hed++];
		if(dp[tmp.i][tmp.j]<tmp.c) continue;
		bool flag=true;
		for(int i=0;i<n;i++){
			if(tir[tmp.i][i]==0) {flag=false; break ;}
		}
		if(flag) ans=min(ans,dp[tmp.i][tmp.j]);
		u=tmp.j;
		for(int e=head[tmp.j];e!=-1;e=edge[e].next){
			v=edge[e].v;
			if(v==u||tir[tmp.i][v]==2) continue;
			int states=tmp.i+s[v];
			if(dp[states][v]>tmp.c+edge[e].c){
				dp[states][v]=tmp.c+edge[e].c;
				que[tail++]=Status(states,v,dp[states][v]);
			}
		}
	}
	printf("%d\n",ans==inf?-1:ans);
}

int main(){
	int u,v,c;
	init();
	while(scanf("%d%d",&n,&m)!=EOF){
		memset(head,-1,sizeof(head));
		tot=0;
		for(int i=0;i<m;i++){
			scanf("%d%d%d",&u,&v,&c);
			u--; v--;
			addedge(u,v,c);
			addedge(v,u,c);
		}
		for(int i=0;i<s[n];i++){
			for(int j=0;j<n;j++)
			dp[i][j]=inf;
		}
		hed=tail=0;
		for(int i=0;i<n;i++){
			int st=s[i];
			dp[st][i]=0;
			que[tail++]=Status(st,i,0);
		}
		slove();
	}
	return 0;
}