Submission #1066645

#	Time	Username	Problem	Language	Result	Execution time	Memory
1066645		12345678	Alternating Current (BOI18_alternating)	C++17	0 / 100	1 ms	600 KiB

alternating

#include <bits/stdc++.h>

using namespace std;

const int nx=20;

int n, m, a[nx], b[nx], dp[nx], vl;

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n>>m;
    for (int i=0; i<m; i++) cin>>a[i]>>b[i];
    for (int msk=0; msk<(1<<m); msk++)
    {
        for (int i=0; i<n; i++) dp[i]=0;
        for (int i=0; i<m; i++)
        {
            if (msk&(1<<i)) vl=2;
            else vl=1;
            if (a[i]<=b[i]) 
            {
                for (int j=a[i]; j<=b[i]; j++) dp[j]|=vl;
            }
            else
            {
                for (int j=1; j<=b[i]; j++) dp[j]|=vl;
                for (int j=a[i]; j<=n; j++) dp[j]|=vl;
            }
        }
        int f=0;
        for (int i=1; i<=n; i++) if (dp[i]!=3) f=1;
        if (!f)
        {
            for (int i=0; i<m;i ++) cout<<((msk&(1<<i))>0);
            return 0;
        }
    }
    cout<<"impossible";
}

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