题解 | 小心火烛的歪

#include <bits/stdc++.h>
using namespace std;
#define endl "\n"
#define pb push_back
using vi = vector<int>;
using vs = vector<string>;
template <typename T>
void out(T& a) { for (auto& x : a) { cout << x << " "; }cout << endl; }
void solve() {
    int n, m, q;cin >> n >> m >> q;
    vs a(n);
    for (int i = 0;i < n;i++) {
        cin >> a[i];
    }
    vector<vs> b(q, vs(n));
    for (int i = 0;i < q;i++) {
        for (int j = 0;j < n;j++) {
            cin >> b[i][j];
        }
    }
    int mn = 1e9;
    vi ans;
    for (int i = 0;i < 1 << q;i++) {
        vs c(n, string(m, '1'));
        vi t;
        for (int j = 0;j < q;j++) {
            if (((i >> j) & 1) == 1) {
                t.pb(j + 1);
                for (int ii = 0;ii < n;ii++) {
                    for (int jj = 0;jj < m;jj++) {
                        if (b[j][ii][jj] == '1')
                            c[ii][jj] = '0';
                    }
                }
            }
        }
        if (c == a) {
            if (t.size() < mn) {
                mn = t.size();
                ans = t;
            }
        }
    }
    if (mn != 1e9) {
        cout << mn << endl;
        out(ans);
        return;
    }
    cout << -1 << endl;
}


/*

*/


signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);cout.tie(nullptr);
    int t = 1;
    //cin >> t;
    for (int i = 1; i <= t; i++) {
        //cout << "----Test " << i << "----" << endl;
        solve();
    }
    return 0;
}

数据范围较小，可以直接位运算枚举，记录最小符合的方案数输出