Submission #876886

#	Time	Username	Problem	Language	Result	Execution time	Memory
876886		hyakup	Pipes (CEOI15_pipes)	C++17	10 / 100	2706 ms	65536 KiB

pipes

#include <bits/stdc++.h>
using namespace std;
#define bug(x) cout << #x << " " << x << endl;

const int maxn = 1e5 + 10;

vector<int> v, pai( maxn ), tam( maxn, 1 ), tempo( maxn, -1 );
vector<pair< int, int >> edge( maxn, pair< int, int>( -1, -1 ) );

int find( int a ){ return (( a == pai[a] ) ? a : find(pai[a]) ); }
bool query( int a, int b ){
     v.clear();
     while( (pai[a] != a || pai[b] != b) && a != b ){
          if( tempo[a] > tempo[b] ){
               if( edge[a] != make_pair( -1, -1 ) ) v.push_back(a);
               a = pai[a];
          }
          else{
               if( edge[b] != make_pair( -1, -1 ) ) v.push_back(b);
               b = pai[b];
          }
     }
     return ( a == b );
}

void join( int a, int b, int t ){
     int _a = find(a);
     int _b = find(b);
     if( tam[_a] < tam[_b] ) swap( _a, _b );
     tam[_a] += tam[_b];
     pai[_b] = _a;
     tempo[_b] = t;
     edge[_b] = make_pair(a, b);
}

int main(){
     int n, m; cin >> n >> m;
     for( int i = 1; i <= n; i++ ) pai[i] = i;
     while( m-- ){
          int a, b; cin >> a >> b;
          if( !query( a, b ) ) join( a, b, m  + 10 );
          else for( int x : v ) edge[x] = make_pair( -1, -1 );
     }
     for( int i = 1; i <= n; i++ ){
          if( edge[i] != make_pair( -1, -1 ) ) cout << edge[i].first << " " << edge[i].second << endl;
     }
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 10 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10