HackerEarth Minimize nodes problem solution

#include<bits/stdc++.h>
using namespace std;
int solve(vector<int> a)
{
    int ans = 0;
    for(int i = 0; i < a.size() ; i++)
        ans += a[i];
    return ans;
}
int solve(vector<int> a, vector<int> b)
{
    int ans = 0;
    for(int i = 0; i < a.size() ; i++){
        int mn = min(a[i], b[i]);
        ans += mn;
        a[i] -= mn;
        b[i] -= mn;
    }
    return ans + solve(a) + solve(b);
}
int solve(vector<int> a, vector<int> b, vector<int> c)
{
    int ans = 0;
    for(int i = 0; i < a.size() ; i++){
        int mn = min({a[i], b[i], c[i]});
        ans += mn;
        a[i] -= mn;
        b[i] -= mn;
        c[i] -= mn;
    }
    int val = solve(a) + solve(b, c);
    val = min(val, solve(b) + solve(a, c));
    val = min(val, solve(c) + solve(a, b));
    return ans + val;
}
int solve(vector<int> a, vector<int> b, vector<int> c, vector<int> d)
{
    int ans = 0;
    for(int i = 0; i < a.size() ; i++){
        int mn = min({a[i], b[i], c[i], d[i]});
        ans += mn;
        a[i] -= mn;
        b[i] -= mn;
        c[i] -= mn;
        d[i] -= mn;
    }
    int val = solve(a) + solve(b, c, d);
    val = min(val, solve(b) + solve(a, c, d));
    val = min(val, solve(c) + solve(a, b, d));
    val = min(val, solve(d) + solve(a, b, c));
    val = min(val, solve(a, b) + solve(c, d));
    val = min(val, solve(a, c) + solve(b, d));
    val = min(val, solve(a, d) + solve(b, c));
    return ans + val;
}
long long solve (int N, vector<vector<int> > cnt) {
    // Write your code here
    int i, j, k, l;
    int ans = 1e9;
    assert(4 <= N && N <= 20);
    for(i = 0; i < N ; i++)
        for(j = 0; j < 26 ; j++)
            assert(0 <= cnt[i][j] && cnt[i][j] <= 100000);
    for(i = 0; i < N ; i++)
        for(j = i+1; j < N ; j++)
            for(k = j + 1 ; k < N ; k++)
                for(l = k + 1 ; l < N ; l++){
                    ans = min(ans, solve(cnt[i], cnt[j], cnt[k], cnt[l]));
                }
    return (1 + ans);
}

int main() {

    ios::sync_with_stdio(0);
    cin.tie(0);
    int T;
    cin >> T;
    assert(1 <= T && T <= 5);
    for(int t_i = 0; t_i < T; t_i++)
    {
        int N;
        cin >> N;
        vector<vector<int> > cnt(N, vector<int>(26));
        for (int i_cnt = 0; i_cnt < N; i_cnt++)
        {
            for(int j_cnt = 0; j_cnt < 26; j_cnt++)
            {
                cin >> cnt[i_cnt][j_cnt];
            }
        }

        long long out_;
        out_ = solve(N, cnt);
        cout << out_;
        cout << "n";
    }
}