Submission #832512

#	Time	Username	Problem	Language	Result	Execution time	Memory
832512		LucaIlie	Port Facility (JOI17_port_facility)	C++17	22 / 100	6063 ms	40032 KiB

port_facility

#include <bits/stdc++.h>

using namespace std;

const int MAX_N = 1e6;
const int MOD = 1e9 + 7;

bool vis[MAX_N], side[MAX_N];
int l[MAX_N], r[MAX_N];
vector<int> edges[MAX_N];
bool bipartit = true;

void checkBipartit( int u ) {
    vis[u] = true;
    for ( int v: edges[u] ) {
        if ( vis[v] ) {
            if ( side[u] == side[v] )
                bipartit = false;
        } else {
            side[v] = side[u] ^ 1;
            checkBipartit( v );
        }
    }
}

int main() {
    int n;

    cin >> n;
    for ( int i = 0; i < n; i++ )
        cin >> l[i] >> r[i];

    for ( int i = 0; i < n; i++ ) {
        for ( int j = i + 1; j < n; j++ ) {
            if ( (l[i] <= l[j] && r[i] <= r[j] && r[i] >= l[j]) || (l[j] <= l[i] && r[j] <= r[i] && r[j] >= l[i]) ) {
                edges[i].push_back( j );
                edges[j].push_back( i );
            }
        }
    }

    int comp = 0;
    for ( int u = 0; u < n; u++ ) {
        if ( !vis[u] ) {
            side[u] = 0;
            checkBipartit( u );
            comp++;
        }
    }

    if ( bipartit ) {
        int ans = 1;
        for ( int i = 0; i < comp; i++ )
            ans = ans * 2 % MOD;
        cout << ans;
    } else
        cout << 0;

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 0 / 56
• Subtask 4: 0 / 22