luogu3959 宝藏

Posted 2020-10-24 poorpool

状压搜索轻轻松松就过了……考场上代码太丑了T了几个点

#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;
int n, m, uu, vv, ww, w[15][15], dis[15], dp[100005], ans;
const int oo=0x3f3f3f3f;
void dfs(int x){
    for(int i=1; i<=n; i++)
        if(x&(1<<(i-1)))
            for(int j=1; j<=n; j++)
                if(!(x&(1<<(j-1))) && w[i][j]<oo)
                    if(dp[x|(1<<(j-1))]>dp[x]+dis[i]*w[i][j]){
                        int t=dis[j];
                        dis[j] = dis[i] + 1;
                        dp[x|(1<<(j-1))] = dp[x] + dis[i] * w[i][j];
                        dfs(x|(1<<(j-1)));
                        dis[j] = t;
                    }
}
int main(){
    cin>>n>>m;
    ans = oo;
    memset(w, 0x3f, sizeof(w));
    for(int i=1; i<=m; i++){
        scanf("%d %d %d", &uu, &vv, &ww);
        w[uu][vv] = w[vv][uu] = min(w[vv][uu], ww);
    }
    for(int i=1; i<=n; i++){
        memset(dis, 0x3f, sizeof(dis));
        memset(dp, 0x3f, sizeof(dp));
        dp[1<<(i-1)] = 0;
        dis[i] = 1;
        dfs(1<<(i-1));
        ans = min(ans, dp[(1<<n)-1]);
    }
    cout<<ans;
    return 0;
}