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Submission #117744

# Submission time Handle Problem Language Result Execution time Memory
117744 2019-06-17T07:20:53 Z minhtung0404 Pipes (CEOI15_pipes) C++17
100 / 100
 4027 ms 13048 KB 
//https://oj.uz/problem/view/CEOI15_pipes

#include<bits/stdc++.h>
const int N = 1e5 + 5;
using namespace std;

vector <int> G[N];
int n, m, low[N], num[N], cnt;

struct dsu{
    int pset[N];

    void init(){
        for (int i = 1; i <= n; i++) pset[i] = i;
    }

    int find(int i) {return ((pset[i] == i) ? i : pset[i] = find(pset[i]));}

    bool Union(int i, int j){
        int u = find(i), v = find(j);
        if (u == v) return false;
        pset[u] = v;
        G[i].push_back(j);
        G[j].push_back(i);
        return true;
    }
} a[2];

void dfs(int u, int p){
    num[u] = low[u] = ++cnt; bool ck = false;
    for (auto v : G[u]){
        if (v == p && !ck) {ck = true; continue;}
        if (num[v]){
            low[u] = min(low[u], num[v]);
        }
        else{
            dfs(v, u);
            low[u] = min(low[u], low[v]);
        }
    }
    if (u != p && low[u] >= num[u]) cout << u << " " << p << "\n";
}

int main(){
    cin >> n >> m;
    a[0].init(); a[1].init();
    for (int i = 1; i <= m; i++){
        int u, v; cin >> u >> v;
        if (!a[0].Union(u, v)) a[1].Union(u, v);
    }
    for (int i = 1; i <= n; i++) if (!num[i]) dfs(i, i);
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2688 KB Output is correct
2 Correct 4 ms 2688 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 3200 KB Output is correct
2 Correct 11 ms 3072 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 293 ms 3012 KB Output is correct
2 Correct 283 ms 2876 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 495 ms 3720 KB Output is correct
2 Correct 578 ms 3300 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 922 ms 5148 KB Output is correct
2 Correct 718 ms 4836 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1181 ms 9932 KB Output is correct
2 Correct 1046 ms 7116 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2029 ms 11064 KB Output is correct
2 Correct 1769 ms 8576 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2571 ms 13048 KB Output is correct
2 Correct 2356 ms 8936 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3050 ms 13000 KB Output is correct
2 Correct 2967 ms 8916 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4027 ms 12484 KB Output is correct
2 Correct 3680 ms 10184 KB Output is correct