Submission #527415

#	Time	Username	Problem	Language	Result	Execution time	Memory
527415		joelau	Pipes (CEOI15_pipes)	C++14	70 / 100	1079 ms	20920 KiB

pipes

#include <bits/stdc++.h>
using namespace std;

int N,M,ufds[100005], ufds1[100005], depth[100005], low[100005], p[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 d) {
    depth[x] = d, low[x] = d;
    bool b = true;
    for (int v: lst[x]) {
        if (depth[v] == -1) {
            p[v] = x;
            dfs(v,d+1);
            if (low[v] > depth[x]) cout << x+1 << ' ' << v+1 << '\n';
            low[x] = min(low[x],low[v]);
        }
        else if (v == p[x] && 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,0);

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10