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Submission #168217

# Submission time Handle Problem Language Result Execution time Memory
168217 2019-12-12T02:49:56 Z gs18103 Pipes (CEOI15_pipes) C++14
90 / 100
 1524 ms 23800 KB 
#include <bits/stdc++.h>
#define fi first
#define se second
#define all(v) v.begin(), v.end()
#define eb emplace_back
#define em emplace

using namespace std;
typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;

const int MAX = 100010;
const int INF = 1 << 30;
const ll LINF = 1LL << 60;

struct UFT {
    int p[MAX];
    UFT(int n) {
        for(int i = 1; i <= n; i++) p[i] = i;
    }

    int find(int x) {
        return p[x] == x ? p[x] : p[x] = find(p[x]);
    }
    void uni(int x, int y) {
        p[find(x)] = find(y);
    }
};

vector <int> g[MAX];
int low[MAX], ord[MAX], pa[MAX], cnt = 0;

void dfs(int x) {
    ord[x] = low[x] = ++cnt;
    bool was = false;
    for(auto i : g[x]) {
        if(i == pa[x] && !was) {
            was = true;
            continue;
        }
        if(ord[i] == 0) {
            pa[i] = x;
            dfs(i);
            low[x] = min(low[x], low[i]);
            if(low[i] > ord[x]) cout << x << ' ' << i << '\n';
        }
        else if(ord[i] < ord[x]) {
            low[x] = min(low[x], ord[i]);
        }
    }
}

int main() {
    ios::sync_with_stdio(false); cin.tie(0);

    int n, m;
    cin >> n >> m;
    UFT t1(n), t2(n);
    for(int i = 1; i <= m; i++) {
        int u, v; cin >> u >> v;
        if(t1.find(u) != t1.find(v)) {
            t1.uni(u, v);
            g[u].eb(v), g[v].eb(u);
        }
        else if(t2.find(u) != t2.find(v)) {
            t2.uni(u, v);
            g[u].eb(v), g[v].eb(u);
        }
    }
    for(int i = 1; i <= n; i++) {
        if(ord[i] == 0) dfs(i);
    }
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2680 KB Output is correct
2 Correct 4 ms 2680 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 3192 KB Output is correct
2 Correct 8 ms 3064 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 129 ms 3044 KB Output is correct
2 Correct 126 ms 2936 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 214 ms 3848 KB Output is correct
2 Correct 247 ms 3320 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 368 ms 5496 KB Output is correct
2 Correct 313 ms 5112 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 526 ms 10984 KB Output is correct
2 Correct 466 ms 7468 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 798 ms 12344 KB Output is correct
2 Correct 737 ms 9464 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1052 ms 14504 KB Output is correct
2 Correct 991 ms 9536 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1260 ms 14456 KB Output is correct
2 Correct 1302 ms 9492 KB Output is correct

Subtask #10
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1524 ms 13808 KB Output is correct
2 Runtime error 1479 ms 23800 KB Memory limit exceeded (if you are sure your verdict is not MLE, please contact us)