스타트와 링크 with 비트마스크

https://www.acmicpc.net/problem/14889

14889번: 스타트와 링크

 

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int s[20][20];
int n;
 
int main() {
    cin >> n;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            cin >> s[i][j];
        }
    }
    int ans = -1;
    for (int i = 0; i < (1 << n); i++)
    {
        vector<int> first, second;
 
        //1번팀 0번팀
        for (int j = 0; j < n; j++)
        {
            if (i & (1 << j))
                first.push_back(j);
            else
                second.push_back(j);
        }
 
        if (first.size() != n / 2) continue;
        int t1 = 0;
        int t2 = 0;
        for (int l1 = 0; l1 < n / 2; l1++) 
        {
            for (int l2 = 0; l2 < n / 2; l2++) 
            {
                if (l1 == l2) continue;
                t1 += s[first[l1]][first[l2]];
                t2 += s[second[l1]][second[l2]];
            }
        }
 
        int diff = t1 - t2;
        if (diff < 0) diff = -diff;
        if (ans == -1 || ans > diff)
            ans = diff;
    }
    
    cout << ans << '\n';
}