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Submission #527421

# Submission time Handle Problem Language Result Execution time Memory
527421 2022-02-17T11:26:33 Z joelau Pipes (CEOI15_pipes) C++14
100 / 100
 943 ms 16044 KB 
#include <bits/stdc++.h>
using namespace std;

int N,M,ufds[100005], ufds1[100005], depth[100005], low[100005];
vector<int> lst[100005];

int findSet(int i) {
    return ufds[i] == i ? i : ufds[i] = findSet(ufds[i]);
}

void unionSet (int i, int j) {
    int a = findSet(i), b = findSet(j);
    if (a != b) ufds[a] = b;
}

int findSet1(int i) {
    return ufds1[i] == i ? i : ufds1[i] = findSet1(ufds1[i]);
}

void unionSet1 (int i, int j) {
    int a = findSet1(i), b = findSet1(j);
    if (a != b) ufds1[a] = b;
}

void dfs (int x, int p, int d) {
    depth[x] = d, low[x] = d;
    bool b = true;
    for (int v: lst[x]) {
        if (depth[v] == -1) {
            dfs(v,x,d+1);
            if (low[v] > depth[x]) cout << x+1 << ' ' << v+1 << '\n';
            low[x] = min(low[x],low[v]);
        }
        else if (v == p && b) b = false;
        else low[x] = min(low[x],depth[v]);
    }
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);
    cin >> N >> M;
    for (int i = 0; i < N; ++i) ufds[i] = i, ufds1[i] = i;
    for (int i = 0; i < M; ++i) {
        int u,v; cin >> u >> v; u--, v--;
        if (findSet(u) != findSet(v)) {
            unionSet(u,v);
            lst[u].push_back(v), lst[v].push_back(u);
        }
        else if (findSet1(u) != findSet1(v)) {
            unionSet1(u,v);
            lst[u].push_back(v), lst[v].push_back(u);
        }
    }
    memset(depth,-1,sizeof(depth));
    for (int i = 0; i < N; ++i) if (depth[i] == -1) dfs(i,-1,0);

    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 3020 KB Output is correct
2 Correct 2 ms 3020 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 3504 KB Output is correct
2 Correct 5 ms 3248 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 81 ms 3356 KB Output is correct
2 Correct 81 ms 3208 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 143 ms 4164 KB Output is correct
2 Correct 161 ms 3628 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 231 ms 5824 KB Output is correct
2 Correct 197 ms 5600 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 319 ms 11388 KB Output is correct
2 Correct 284 ms 7376 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 495 ms 12588 KB Output is correct
2 Correct 466 ms 9284 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 640 ms 14864 KB Output is correct
2 Correct 668 ms 11232 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 798 ms 14860 KB Output is correct
2 Correct 769 ms 11952 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 943 ms 14228 KB Output is correct
2 Correct 908 ms 16044 KB Output is correct