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Submission #1099017

# Submission time Handle Problem Language Result Execution time Memory
1099017 2024-10-10T12:16:48 Z nikolashami Pipes (CEOI15_pipes) C++17
50 / 100
 762 ms 60080 KB 
#include <bits/stdc++.h>
using namespace std;
mt19937 rng(time(0));

const int mxN=1e5+2;
vector<int>adj[mxN];
int ln[mxN],dp[mxN],vv[mxN];

int finde(int &x){
	return x==ln[x]?x:ln[x]=finde(ln[x]);
}

void merge(int u,int v){
	ln[finde(u)]=finde(v);
}

void dfs(int u,int p){
	vv[u]=1;
	for(int&v:adj[u]){
		if(!(v^p))
			continue;
		dfs(v,u);
		dp[u]^=dp[v];
	}
}

void res(int u,int p){
	vv[u]=1;
	for(int&v:adj[u]){
		if(!(v^p))
			continue;
		res(v,u);
		if(!dp[v])
			cout<<u<<' '<<v<<'\n';
	}
}

signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    
    int n,m;
    cin>>n>>m;

    for(int i=0;i<n+2;++i)
    	ln[i]=i;

    for(int i=0,u,v;i<m;++i){
    	cin>>u>>v;
    	if(finde(u)==finde(v)){
    		int xx=rng();
    		dp[u]^=xx;
    		dp[v]^=xx;
    	}else{
    		merge(u,v);
    		adj[u].push_back(v);
    		adj[v].push_back(u);
    	}
    }

	for(int i=0;i<n+2;++i)
		vv[i]=0;

    for(int fi=1;fi<=n;++fi){
    	if(vv[fi])
    		continue;
    	dfs(fi,0);
    }

	for(int i=0;i<n+2;++i)
		vv[i]=0;

    for(int fi=1;fi<=n;++fi){
    	if(vv[fi])
    		continue;
    	res(fi,0);
    }
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2652 KB Output is correct
2 Correct 1 ms 2640 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2908 KB Output is correct
2 Correct 3 ms 2908 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 67 ms 2940 KB Output is correct
2 Correct 59 ms 2944 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 97 ms 3176 KB Output is correct
2 Correct 115 ms 3160 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 174 ms 3732 KB Output is correct
2 Correct 150 ms 3920 KB Output is correct

Subtask #6
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 217 ms 5712 KB Output is correct
2 Runtime error 225 ms 19540 KB Memory limit exceeded
3 Halted 0 ms 0 KB -

Subtask #7
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 355 ms 6116 KB Output is correct
2 Runtime error 387 ms 23188 KB Memory limit exceeded
3 Halted 0 ms 0 KB -

Subtask #8
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 498 ms 6952 KB Output is correct
2 Runtime error 486 ms 38536 KB Memory limit exceeded
3 Halted 0 ms 0 KB -

Subtask #9
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 625 ms 6848 KB Output is correct
2 Runtime error 586 ms 46964 KB Memory limit exceeded
3 Halted 0 ms 0 KB -

Subtask #10
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 762 ms 6632 KB Output is correct
2 Runtime error 750 ms 60080 KB Memory limit exceeded
3 Halted 0 ms 0 KB -