Submission #1298618

#	Time	Username	Problem	Language	Result	Execution time	Memory
1298618		tuongll	Alternating Current (BOI18_alternating)	C++20	13 / 100	2592 ms	2144 KiB

alternating

#include <bits/stdc++.h>
using namespace std;

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int n, m; cin >> n >> m;
    vector<pair<int, int>> segments;
    for (int i = 1, a, b; i <= m; ++i){
        cin >> a >> b;
        if (a > b) b += n;
        segments.emplace_back(a, b);
    }

    for (int mask = 0; mask < (1 << m); ++mask){
        vector<int> val(2 * n + 1);
        for (int i = 0; i < m; ++i){
            auto [a, b] = segments[i];
            if (mask >> i & 1){
                for (int x = a; x <= b; ++x)
                    val[x] |= 1;
            }
            else {
                for (int x = a; x <= b; ++x)
                    val[x] |= 2;
            }
        }

        bool flag = true;
        for (int i = 1; i <= n; ++i)
            flag &= ((val[i] | val[i + n]) == 3);
        
        if (flag){
            for (int i = 0; i < m; ++i)
                cout << (mask >> i & 1);
            return 0;
        }
    }

    cout << "impossible";
}

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