Submission #290631

#	Time	Username	Problem	Language	Result	Execution time	Memory
290631		davooddkareshki	Pipes (CEOI15_pipes)	C++17	30 / 100	2650 ms	65540 KiB

pipes

#include<bits/stdc++.h>

using namespace std;

//#define int long long
#define F first
#define S second
#define pii pair<int,int>
#define mpr make_pair

typedef long long ll;

const int maxn = 1e5+10;
const int mod = 1e9+7;
const int inf = 1e9+10;

int n, m;
vector<int> g[maxn], comp;
bitset<maxn> mark;
int h[maxn], lo[maxn], par[maxn], Root;

void dfs(int v)
{
	mark[v] = 1;
	lo[v] = h[v];
	comp.push_back(v);
	for(auto u : g[v]) if(mark[u] && u != par[v]) lo[v] = min(lo[v],h[u]);
	for(auto u : g[v])
		if(!mark[u])
		{
			h[u] = h[v] + 1;
            par[u] = v;
			dfs(u);
			lo[v] = min(lo[v], lo[u]);
		}
        else
            if(par[u] == v)
                lo[u] = min(lo[u],h[v]);
}

signed main()
{
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);

    cin>> n >> m;
    for(int i = 1, u, v; i <= m; i++)
    {
        cin>> u >> v;
        g[u].push_back(v);
        g[v].push_back(u);
    }

    for(int i = 1; i <= n; i++)
        if(!mark[i])
        {
            Root = i;
            comp.clear();
            dfs(i);
            for(auto v : comp)
                if(v != Root && lo[v] >= h[v])
                    cout<< v <<" "<< par[v] <<"\n";
        }
}
/*
10 11
1 7
1 8
1 6
2 8
6 7
5 8
2 5
2 3
2 4
3 4
10 9
*/

• 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