Submission #669612

#	Time	Username	Problem	Language	Result	Execution time	Memory
669612		Iliya_	Pipes (CEOI15_pipes)	C++17	100 / 100	955 ms	15436 KiB

pipes

// IN THE NAME OF GOD
#include<bits/stdc++.h>
#pragma GCC optimize ("O2,unroll-loops")
#define endl '\n';
#define file_reading freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout);
using namespace std;
typedef long long ll;
typedef long double dll;
typedef unsigned long long ull;
// Variables
const int B = 100000 + 7;
int par1[B];
int par2[B];
int n,m,a,b,one,two;
vector<int> g[B];
bool seen[B];
int father[B];
int dist[B];
int val[B];
// main functions
int get_root1(int v){
     return (par1[v] == v ? v : par1[v] = get_root1(par1[v]));
}
int get_root2(int v){
     return (par2[v] == v ? v : par2[v] = get_root2(par2[v]));
}
bool merge1(int v, int u){
     one = get_root1(v);
     two = get_root1(u);
     if (one == two){return 0;}
     par1[one] = two;
     return 1;
}
bool merge2(int v, int u){
     one = get_root2(v);
     two = get_root2(u);
     if (one == two){return 0;}
     par2[one] = two;
     return 1;
}
void dfs(int vv){
     seen[vv] = 1;
     for(auto u : g[vv]){
          if (seen[u] == 0){
               father[u] = vv;
               dist[u] = dist[vv] + 1;
               dfs(u);
               val[vv] += val[u];
               int cnt = 0;
               for(auto ind : g[vv]){if (ind == u){cnt++;}}
               if (val[u] == 0 && cnt == 1){cout << vv << " " << u << endl;}
          }
          else if (father[u] != vv && father[vv] != u && dist[u] < dist[vv]){
               val[u]--;
               val[vv]++;
          }
     }
}
int32_t main(){
	ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);

	cin >> n >> m;
	for(int i=1; i<=n; i++){par1[i] = par2[i] = i;}
	for(int i=1; i<=m; i++){
          cin >> a >> b;
          if (merge1(a,b)){
               g[a].push_back(b);
               g[b].push_back(a);
          }
          else if (merge2(a,b)){
               g[a].push_back(b);
               g[b].push_back(a);
          }
	}
     for(int i=1; i<=n; i++){
          if (seen[i] == 0){
               father[i] = 0;
               dist[i] = 0;
               dfs(i);
          }
     }

	return 0;
}

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