Submission #882513

#	Time	Username	Problem	Language	Result	Execution time	Memory
882513		LucaIlie	Jail (JOI22_jail)	C++17	72 / 100	3783 ms	1048576 KiB

jail

#include <bits/stdc++.h>

using namespace std;

struct prisoner {
    int b, w;
};

const int MAX_N = 1.2e5;
const int MAX_M = MAX_N;
int parent[MAX_N + 1], depth[MAX_N + 1], bedroom[MAX_N + 1], workroom[MAX_N + 1], in[MAX_N + 1];
vector <int> edges[MAX_N + 1], g[MAX_M + 1];
prisoner prisoners[MAX_M + 1];

void dfs( int u, int p ) {
    depth[u] = depth[p] + 1;
    parent[u] = p;
    for ( int v: edges[u] ) {
        if ( v == p )
            continue;
        dfs( v, u );
    }
}

int main() {
    int t;

    cin >> t;
    while ( t-- ) {
        int n, m;

        cin >> n;
        for ( int v = 1; v <= n; v++ ) {
            edges[v].clear();
            workroom[v] = 0;
            bedroom[v] = 0;
        }
        for ( int i = 0; i < n - 1; i++ ) {
            int u, v;
            cin >> u >> v;
            edges[u].push_back( v );
            edges[v].push_back( u );
        }
        cin >> m;
        for ( int i = 1; i <= m; i++ ) {
            g[i].clear();
            in[i] = 0;
        }
        for ( int i = 1; i <= m; i++ )
            cin >> prisoners[i].b >> prisoners[i].w;

        dfs( 1, 0 );

        for ( int i = 1; i <= m; i++ ) {
            bedroom[prisoners[i].b] = i;
            workroom[prisoners[i].w] = i;
        }
        for ( int i = 1; i <= m; i++ ) {
            int u = prisoners[i].b, v = prisoners[i].w;

            if ( depth[u] < depth[v] )
                swap( u, v );

            while ( depth[u] > depth[v] ) {
                if ( bedroom[u] != 0 && bedroom[u] != i )
                    g[bedroom[u]].push_back( i );
                if ( workroom[u] != 0 && workroom[u] != i )
                    g[i].push_back( workroom[u] );
                u = parent[u];
            }

            while ( u != v ) {
                if ( bedroom[u] != 0 && bedroom[u] != i )
                    g[bedroom[u]].push_back( i );
                if ( workroom[u] != 0 && workroom[u] != i )
                    g[i].push_back( workroom[u] );
                if ( bedroom[v] != 0 && bedroom[v] != i )
                    g[bedroom[v]].push_back( i );
                if ( workroom[v] != 0 && workroom[v] != i )
                    g[i].push_back( workroom[v] );
                u = parent[u];
                v = parent[v];
            }
            if ( bedroom[u] != 0 && bedroom[u] != i )
                g[bedroom[u]].push_back( i );
            if ( workroom[u] != 0 && workroom[u] != i )
                g[i].push_back( workroom[u] );
        }
        for ( int i = 1; i <= m; i++ ) {
            sort( g[i].begin(), g[i].end() );
            g[i].resize( unique( g[i].begin(), g[i].end() ) - g[i].begin() );
            for ( int j: g[i] )
                in[j]++;
        }

        queue <int> q;
        for ( int i = 1; i <= m; i++ ) {
            if ( in[i] == 0 )
                q.push( i );
        }
        int pasi = 0;
        while ( !q.empty() ) {
            int u = q.front();
            q.pop();
            pasi++;

            for ( int v: g[u] ) {
                in[v]--;
                if ( in[v] == 0 )
                    q.push( v );
            }
        }

        cout << (pasi == m ? "Yes\n" : "No\n");
    }

    return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 5 / 5
• Subtask 3: 16 / 16
• Subtask 4: 28 / 28
• Subtask 5: 12 / 12
• Subtask 6: 11 / 11
• Subtask 7: 0 / 23