oj.uz

Submission #959305

# Submission time Handle Problem Language Result Execution time Memory
959305 2024-04-07T23:18:19 Z Cyber_Wolf Pipes (CEOI15_pipes) C++17
60 / 100
 997 ms 61076 KB 
#include <bits/stdc++.h>
 
using namespace std;
 
const int N = 1e5+5;
 
vector<int> adj[N];
int tin[N], par[N][2], low[N];
 
int get1(int src)
{
	return par[src][0] = (src == par[src][0] ? src : get1(par[src][0]));
}
 
int get2(int src)
{
	return par[src][1] = (src == par[src][1] ? src : get2(par[src][1]));
}
 
int n, m, tmp, pa = -1;
void dfs(int src)
{
	bool a = false;
	tin[src] = low[src] = ++tmp;
	for(auto it : adj[src])
	{
		if(it == pa && !a)
		{
			a = true;
			continue;
		}
		if(tin[it])
		{
			low[src] = min(low[src], tin[it]);
			continue;
		}
		swap(pa, src);
		dfs(it);
		swap(pa, src);
		low[src] = min(low[src], low[it]);
		if(low[it] > tin[src])
		{
			printf("%d %d\n", src, it);
		}
	}
	return ;
}
 
int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	
	scanf("%d%d", &n, &m);
	for(int i = 1; i <= n; i++)	par[i][0] = par[i][1] = i;
	int u, v, pU, pV;
	while(m--)
	{
		scanf("%d%d", &u, &v);
		pU = get1(u), pV = get1(v);
		if(pU != pV)
		{
			par[pU][0] = pV;
			adj[u].push_back(v), adj[v].push_back(u);
		}
		else{
			pU = get2(u), pV = get2(v);
			if(pU != pV)
			{
				par[pU][1] = pV;
				adj[u].push_back(v), adj[v].push_back(u);
			}
		}
	}
	for(int i = 1; i <= n; i++)
	{
		if(!tin[i])	dfs(i);
	}
 
    return 0;
}

Compilation message

pipes.cpp: In function 'int main()':
pipes.cpp:55:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   55 |  scanf("%d%d", &n, &m);
      |  ~~~~~^~~~~~~~~~~~~~~~
pipes.cpp:60:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |   scanf("%d%d", &u, &v);
      |   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4188 KB Output is correct
2 Correct 1 ms 4188 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4700 KB Output is correct
2 Correct 4 ms 4444 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 84 ms 4436 KB Output is correct
2 Correct 87 ms 4184 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 142 ms 4948 KB Output is correct
2 Correct 170 ms 4548 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 240 ms 6156 KB Output is correct
2 Correct 194 ms 5972 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 302 ms 10332 KB Output is correct
2 Correct 271 ms 7616 KB Output is correct

Subtask #7
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 484 ms 11260 KB Output is correct
2 Runtime error 486 ms 34676 KB Memory limit exceeded
3 Halted 0 ms 0 KB -

Subtask #8
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 613 ms 13040 KB Output is correct
2 Runtime error 592 ms 40532 KB Memory limit exceeded
3 Halted 0 ms 0 KB -

Subtask #9
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 759 ms 13040 KB Output is correct
2 Runtime error 759 ms 49232 KB Memory limit exceeded
3 Halted 0 ms 0 KB -

Subtask #10
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 913 ms 12572 KB Output is correct
2 Runtime error 997 ms 61076 KB Memory limit exceeded
3 Halted 0 ms 0 KB -