Submission #86697

#	Time	Username	Problem	Language	Result	Execution time	Memory
86697		qwerty12345	Pipes (CEOI15_pipes)	C++14	10 / 100	154 ms	8544 KiB

pipes

//       ###
//      #---##
//  ####-0----##
// ####--------#
//     #--------#
//     ##-------#
//      #-------#
//      #-------#
//     ##--------#
//     #---------# ##### 
//     #-------##-------#######           																																									Ya katala
//     #------#----------------#
//    #------##-----------------#
//    #------##------------------#
//    #-----#---------------------#
//    #-----##---------------------#
//     #------##--------------------#
//      #-------##-------------------#
//       #--------##------------------#
//        ############################ #
//             ||           ||
//             ||           ||
//             ||           ||
//             ||           ||
//          ####|        ####|




#include <bits/stdc++.h>
#include <iostream>

#define for0(i , v) for (int i = 0 ; i < v.size() ; i++)
#define for1(i , n) for (int i = 1 ; i <= n ; i++)
#define AIDS ios_base::sync_with_stdio(0)
#define pb push_back
#define pp pop_back
#define sz(a) a.size()
#define all(x) x.begin() , x.end()
#define F first
#define S second
#define mp make_pair
#define ld long double
#define ll long long
#define pii pair<int, int>
#define in insert
#define vi vector <int>
#define vvi vector <vi>
#define Case "Case " << num << ": "

const int N = 1e6 + 3;
const ll INF = 1e18 + 100;
const int inf = 1e9 + 123;
const int MOD = 1e9 + 7;
const int dx[] = {0 , 1 , 0 , -1 , 0};
const int dy[] = {0 , 0 , 1 , 0 , -1};
const char dd[] = {' ' , 'D' , 'R' , 'U' , 'L'};

using namespace std;

vector <int> g[5001];
vector <pii> q;
bool used[5001];
int tin[5001] , fup[5001] , timer;

void dfs (int v, int p) {
	used[v] = 1;
	tin[v] = fup[v] = timer++;
	for (int to : g[v]) {
		if (to == p) continue;
		if (used[to])	
			fup[v] = min (fup[v], tin[to]);
		else {
			dfs (to, v);
			fup[v] = min (fup[v], fup[to]);
			if (fup[to] > tin[v]) {
				q.pb(mp(min(v , to) , max(v , to)));
			}
		}
	}
}

main () {
//  freopen("input.in", "r", stdin);
//  freopen("output.out", "w", stdout);
	AIDS;
	int n , m;
	cin >> n >> m;
	for (int i = 1 ; i <= m ; i++) {
		int l , r;
		cin >> l >> r;
		g[l].pb(r);
		g[r].pb(l);
	}
	for (int i = 1 ; i <= n ; i++) {
		if (!used[i]) {
			dfs(i , -1);
		}
	}
	for (auto it : q) {
		cout << it.first  << " " << it.second << endl;
	}
}

Compilation message (stderr)

pipes.cpp:83:7: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main () {
       ^

• Subtask 1: 0 / 10
• Subtask 2: 0 / 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