Submission #1113607

#	Time	Username	Problem	Language	Result	Execution time	Memory
1113607		ortsac	Alternating Current (BOI18_alternating)	C++17	13 / 100	27 ms	2384 KiB

alternating

#include <bits/stdc++.h>

using namespace std;

#define pii pair<int, int>
#define fr first
#define se second

int32_t main() {
    int n, m;
    cin >> n >> m;
    vector<pii> r(m);
    for (int i = 0; i < m; i++) {
        cin >> r[i].fr >> r[i].se;
    }
    int ans = -1;
    for (int mask = 0; mask < (1 << m); mask++) {
        vector<vector<int>> qtd(2, vector<int>(n + 2));
        for (int i = 0; i < m; i++) {
            int w = ((mask & (1 << i)) > 0);
            auto u = r[i];
            qtd[w][u.fr]++;
            qtd[w][u.se + 1]--;
            if (u.se < u.fr) {
                qtd[w][1]++;
            }
        }
        for (int j = 0; j < 2; j++) {
            for (int i = 1; i <= n; i++) {
                qtd[j][i] += qtd[j][i - 1];
            }
        }
        bool ok = 1;
        for (int i = 1; i <= n; i++) {
            if (!(qtd[0][i] && qtd[1][i])) ok = 0;
        }
        if (ok) {
            ans = mask;
        }
    }
    if (ans == -1) {
        cout << "impossible\n";
    } else {
        for (int i = 0; i < m; i++) {
            if (ans & (1 << i)) cout << "1";
            else cout << "0";
        }
        cout << "\n";
    }
}

• Subtask 1: 13 / 13
• Subtask 2: 0 / 20
• Subtask 3: 0 / 22
• Subtask 4: 0 / 19
• Subtask 5: 0 / 26