Submission #224134

#	Time	Username	Problem	Language	Result	Execution time	Memory
224134		kshitij_sodani	Pipes (CEOI15_pipes)	C++17	100 / 100	1516 ms	15536 KiB

pipes

#include <iostream>
#include <bits/stdc++.h>
using namespace std;
#define a first
#define b second
#define pb push_back
int n,m;
int par[100001];
int par2[100001];
int find(int no){
	if(par[no]==no){
		return no;
	}
	par[no]=find(par[no]);
	return par[no];
}
int find2(int no){
	if(par2[no]==no){
		return no;
	}
	par2[no]=find2(par2[no]);
	return par2[no];
}
vector<pair<int,int>> adj[100001];
int cco=1;

void dfs(int no,int par3=-1){
	par[no]=cco;
	cco+=1;
	for(auto nn:adj[no]){
		if(par[nn.a]>0){
			if(nn.b==par3){
				continue;
			}
			if(par[nn.a]>=par[no]){
				continue;
			}
			par2[nn.a]-=1;
			par2[no]+=1;
		}
		else{
			dfs(nn.a,nn.b);
			if(par2[nn.a]==0){
			//	if(kk[{no,nn.a}]==1){
					cout<<no+1<<" "<<nn.a+1<<endl;
			//	}
			}
			par2[no]+=par2[nn.a];
		}
	}
}
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cin>>n>>m;
	for(int i=0;i<n;i++){
		par[i]=i;
		par2[i]=i;
	}
	int aa,bb;
	int cc,dd;
	int e,f;
	int ind=0;
	for(int i=0;i<m;i++){
		cin>>cc>>dd;
		cc-=1;
		dd-=1;

		aa=find(cc);
		bb=find(dd);
		/*if(kk[{cc,dd}]==1){
			kk[{cc,dd}]+=1;
			kk[{dd,cc}]+=1;

		}*/
		if(aa==bb){
			e=find2(cc);
			f=find2(dd);
			if(e==f){
				continue;
			}
			adj[cc].pb({dd,ind});
			adj[dd].pb({cc,ind});
		/*	kk[{cc,dd}]+=1;
			kk[{dd,cc}]+=1;*/
			par2[e]=f;
			ind+=1;
		}
		else{
			par[aa]=bb;
			adj[cc].pb({dd,ind});
			adj[dd].pb({cc,ind});
		/*	kk[{cc,dd}]+=1;
			kk[{dd,cc}]+=1;*/
			ind+=1;
		}


	//	cout<<cc<<",,,,,,,,"<<dd<<endl;
	}
	//vis=par
	//dp=par2
	for(int i=0;i<n;i++){
		par[i]=0;
		par2[i]=0;
	}
	for(int i=0;i<n;i++){
		if(par[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