Submission #555408

#	Time	Username	Problem	Language	Result	Execution time	Memory
555408		hidden1	Pipes (CEOI15_pipes)	C++14	20 / 100	967 ms	65536 KiB

pipes

#include <bits/stdc++.h>
using namespace std;
//#pragma GCC optimize ("O3")
//#pragma GCC target ("sse4")

#ifndef LOCAL
#define cerr if(false) cerr
#endif
#define endl "\n"

#define out(x) "[" << #x << "=" << x << "]"
struct debug {
    debug() { cerr << "DEBUGGER: " << endl; }
    ~debug() { cerr << endl << "DEBUGGER_END " << endl; }

    template<class T>
    debug& operator <<(const T x) {
        cerr << x << " ";
        return *this;
    }
};

template<class T> inline ostream &operator <<(ostream &out, const vector<T> &x) {
    for(const auto &it : x) {
        out << it << " ";
    }
    return out;
}
template<class T, class T2> inline ostream &operator <<(ostream &out, const pair<T, T2> &x) {
    return out << x.first << " " << x.second;
}
template<class T, class T2> inline bool chkmax(T &x, const T2 &y) { return x < y ? x = y, 1 : 0; }
template<class T, class T2> inline bool chkmin(T &x, const T2 &y) { return x > y ? x = y, 1 : 0; }

typedef long long ll;
const ll mod = 1e9 + 7;
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~//

const int MAX_N = 1e5 + 10;
vector<pair<int, int> > g[MAX_N];
int low[MAX_N], in[MAX_N], tme = 0;
int n, m;

void dfs(int x, int ind) {
    in[x] = low[x] = ++ tme;

    for(auto it : g[x]) {
        if(low[it.first] == 0) {

            dfs(it.first, it.second);
            chkmin(low[x], low[it.first]);

            if(low[it.first] > in[x]) {
                cout << x << " " << it.first << endl;
            }
        } else if(it.second != ind) {
            chkmin(low[x], in[it.first]);
        }
    }
}

signed main() {
#ifndef LOCAL
    ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#endif

    cin >> n >> m;
    for(int i = 0; i < m; i ++) {
        int a, b;
        cin >> a >> b;
        g[a].push_back({b, i});
        g[b].push_back({a, i});
    }

    for(int i = 1; i <= n; i ++) {
        if(low[i] == 0) {
            dfs(i, -1);
        }
    }

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 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