tsp

// dist[i][j] = i -> j 비용
int n;
int dist[20][20];
int dp[1 << 20][20];
 
int tsp(int cur, int visited){
    if(visited == (1 << n) - 1) return dist[cur][0];
    int& ret = dp[visited][cur];
    if(ret != -1) return ret;
    ret = INF;
    for(int nxt = 0; nxt < n; nxt++){
        if(visited & (1 << nxt)) continue;
        ret = min(ret, dist[cur][nxt] + tsp(nxt, visited | (1 << nxt)));
    }
    return ret;
}
 
// memset(dp, -1, sizeof dp);