Submission #125858

#	Time	Username	Problem	Language	Result	Execution time	Memory
125858		wilwxk	Pipes (CEOI15_pipes)	C++14	30 / 100	3135 ms	65540 KiB

pipes

#include <bits/stdc++.h>
using namespace std;

const int MAXN=1e5+5;
vector<int> g[MAXN];
int pre[MAXN], low[MAXN];
int n, m, tempo;

void dfs(int cur, int p) {
	pre[cur]=low[cur]=++tempo;
	int cont=0;
	for(auto viz : g[cur]) {
		if(viz==p&&cont==0) {
			cont=1; continue;
		}
		if(!pre[viz]) {
			dfs(viz, cur);
			low[cur]=min(low[cur], low[viz]);
			if(low[viz]>pre[cur]) printf("%d %d\n", cur, viz);
		}
		low[cur]=min(low[cur], pre[viz]);
	}
	// printf("%d >> %d %d\n", cur, pre[cur], low[cur]);
}

int main() {
	scanf("%d %d", &n, &m);
	for(int i=1; i<=m; i++) {
		int a, b; scanf("%d %d", &a, &b);
		g[a].push_back(b); g[b].push_back(a);
	}

	for(int i=1; i<=n; i++) if(!pre[i]) dfs(i, i);

}

Compilation message (stderr)

pipes.cpp: In function 'int main()':
pipes.cpp:27:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d", &n, &m);
  ~~~~~^~~~~~~~~~~~~~~~~
pipes.cpp:29:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   int a, b; scanf("%d %d", &a, &b);
             ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10