Submission #498693

#	Time	Username	Problem	Language	Result	Execution time	Memory
498693		LittleCube	Alternating Current (BOI18_alternating)	C++14	0 / 100	16 ms	2144 KiB

alternating

#include <bits/stdc++.h>
#define ll long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define F first
#define S second
using namespace std;

ll N, M;
vector<pii> v;

signed main()
{
    ios::sync_with_stdio(0), cin.tie(0);
    cin >> N >> M;
    for (int i = 1; i <= M; i++)
    {
        int a, b;
        cin >> a >> b;
        v.emplace_back(pii{a, b});
    }
    if (N <= 15)
    {
        for (int mask = 0; mask < (1 << M); mask++)
        {
            bool valid[2] = {1, 1};
            for (int i = 1; i <= N; i++)
            {
                bool exist[2] = {0, 0};
                for (int j = 0; j < M; j++)
                {
                    if ((v[j].F <= i && i <= v[j].S) || (v[j].F > v[j].S && !(v[j].S < i && i < v[j].F)))
                        exist[(mask >> j) & 1] = 1;
                }
                valid[0] &= exist[0];
                valid[1] &= exist[1];
            }
            if (valid[0] && valid[1])
            {
                for (int j = M - 1; j >= 0; j--)
                    cout << ((mask >> j) & 1);
                cout << '\n';
                return 0;
            }
        }
        cout << "impossible\n";
    }
    else
    {
    }
}

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