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Submission #475437

# Submission time Handle Problem Language Result Execution time Memory
475437 2021-09-22T11:41:24 Z MohamedAhmed04 Pipes (CEOI15_pipes) C++14
70 / 100
 5000 ms 8932 KB 
#include <bits/stdc++.h>

using namespace std ;

const int MAX = 1e5 + 10 ;

int P[MAX] , sz[MAX] , P2[MAX] , mark[MAX] , dep[MAX] ;

int n , m ;

vector< vector<int> >adj(MAX) ;

void init()
{
	for(int i = 1 ; i <= n ; ++i)
		P[i] = i , sz[i] = 1 ;
}

int root(int node)
{
	if(P[node] == node)
		return node ;
	return root(P[node]) ;
}

void dfs(int node , int par , bool flag)
{
	for(auto &child : adj[node])
	{
		if(child == par)
			continue ;
		dep[child] = dep[node] + 1 ;
		if(P[node] == child)
			dfs(child , node , mark[node]) ;
		else
			dfs(child , node , mark[child]) ;
	}
	P[node] = P2[node] = par , mark[node] = flag ;
}

void Union(int x , int y)
{
	int a = root(x) ;
	int b = root(y) ;
	if(sz[a] < sz[b])
		swap(a , b) , swap(x , y) ;
	adj[x].push_back(y) , adj[y].push_back(x) ;
	dep[y] = dep[x] + 1 ; 
	dfs(y , x , 0) ;
	sz[a] += sz[b] ;
}

vector<int>v1 , v2 ;

void solve(int x , int y)
{
	while(x != y)
	{
		while(dep[x] >= dep[y] && x != y)
			v1.push_back(x) , mark[x] = 1 , x = P2[x] ;
		while(dep[y] >= dep[x] && x != y)
			v2.push_back(y) , mark[y] = 1 , y = P2[y] ;
	}
	for(auto &node : v1)
		P2[node] = x ;
	for(auto &node : v2)
		P2[node] = y ;
	v1.clear() , v2.clear() ;
}

int main()
{
	ios_base::sync_with_stdio(0) ;
	cin.tie(0) ;
	cin>>n>>m ;
	init() ;
	for(int i = 0 ; i < m ; ++i)
	{
		int x , y ;
		cin>>x>>y ;
		if(root(x) != root(y))
			Union(x , y) ;
		else
			solve(x , y) ;
	}
	for(int i = 1 ; i <= n ; ++i)
	{
		if(!mark[i] && P[i] != i)
			cout<<i<<" "<<P[i]<<"\n" ;
	}
	return 0 ;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2636 KB Output is correct
2 Correct 2 ms 2636 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 3020 KB Output is correct
2 Correct 7 ms 3020 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 233 ms 4008 KB Output is correct
2 Correct 226 ms 3908 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 575 ms 4312 KB Output is correct
2 Correct 572 ms 4420 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 981 ms 5036 KB Output is correct
2 Correct 898 ms 5460 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2424 ms 6340 KB Output is correct
2 Correct 1728 ms 6340 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3835 ms 7872 KB Output is correct
2 Correct 3224 ms 8184 KB Output is correct

Subtask #8
0 / 10.0

# Verdict Execution time Memory Grader output
1 Execution timed out 5022 ms 8932 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #9
0 / 10.0

# Verdict Execution time Memory Grader output
1 Execution timed out 5054 ms 7776 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #10
0 / 10.0

# Verdict Execution time Memory Grader output
1 Execution timed out 5077 ms 7484 KB Time limit exceeded
2 Halted 0 ms 0 KB -