Baekjoon #1497

#include<bits/stdc++.h>

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int N, M; cin >> N >> M;
    vector<long long> V; // 가능한 연주를 bit로 체크해놓고 가지고 있기.
    for(int i = 0; i < N; ++i) {
        string x, y; cin >> x >> y;
        long long available = 0;
        for(char ch: y) {
            available = available << 1 | (ch == 'Y');
        }
        V.emplace_back(available);
    }

    int mx = 0, ans = -1;
    for(int i = 0; i < (1 << N); ++i) {
        long long cur = 0;
        for(int j = 0; j < N; ++j) {
            if(i & (1 << j)) {
                cur |= V[j];
            }
        }
        int cnt = __builtin_popcountll(cur);
        if(cnt > mx) {
            mx = cnt;
            ans = __builtin_popcount(i);
        }
        else if(cnt == mx) {
            ans = min(ans, __builtin_popcount(i));
        }
    }
    cout << ans;

    return 0;
}