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Submission #96162

# Submission time Handle Problem Language Result Execution time Memory
96162 2019-02-06T14:56:55 Z popovicirobert Pipes (CEOI15_pipes) C++14
100 / 100
 1259 ms 13132 KB 
#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
// 217
// 44

using namespace std;

const int MAXN = (int) 1e5;

struct DSU {
    int par[MAXN + 1];
    int n;
    inline void init(int _n) {
        n = _n;
        memset(par, 0, sizeof(par));
    }
    int root(int x) {
        if(par[x] == 0)
            return x;
        return par[x] = root(par[x]);
    }
    inline void join(int x, int y) {
        x = root(x), y = root(y);
        if(x != y) {
            par[x] = y;
        }
    }
}dsu1, dsu2;

vector <int> g[MAXN + 1];

inline void addEdge(int x, int y) {
    g[x].push_back(y);
    g[y].push_back(x);
}

int lvl[MAXN + 1], low[MAXN + 1];

void dfs(int nod, int par) {
    lvl[nod] = lvl[par] + 1;
    low[nod] = lvl[nod];
    int cnt = 0;
    for(auto it : g[nod]) {
        if(lvl[it] == 0) {
            dfs(it, nod);
            low[nod] = min(low[nod], low[it]);
            if(low[it] == lvl[it]) {
                cout << nod << " " << it << "\n";
            }
        }
        else {
            if(it == par) {
                if(cnt == 1) {
                    low[nod] = min(low[nod], lvl[it]);
                }
                cnt++;
            }
            else {
                low[nod] = min(low[nod], lvl[it]);
            }
        }
    }
}

int main() {
    //ifstream cin("B.in");
    //ofstream cout("B.out");
    int i, n, m;
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    cin >> n >> m;
    dsu1.init(n);
    dsu2.init(n);
    for(i = 1; i <= m; i++) {
        int x, y;
        cin >> x >> y;
        if(dsu1.root(x) == dsu1.root(y)) {
            if(dsu2.root(x) != dsu2.root(y)) {
                dsu2.join(x, y);
                addEdge(x, y);
            }
        }
        else {
            dsu1.join(x, y);
            addEdge(x, y);
        }
    }
    for(i = 1; i <= n; i++) {
        if(lvl[i] == 0) {
            dfs(i, 0);
        }
    }
    //cin.close();
    //cout.close();
    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 3456 KB Output is correct
2 Correct 4 ms 3456 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 3840 KB Output is correct
2 Correct 7 ms 3840 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 98 ms 3784 KB Output is correct
2 Correct 96 ms 3704 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 160 ms 4344 KB Output is correct
2 Correct 187 ms 4088 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 284 ms 5756 KB Output is correct
2 Correct 241 ms 5408 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 433 ms 10224 KB Output is correct
2 Correct 365 ms 7364 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 664 ms 11244 KB Output is correct
2 Correct 594 ms 8960 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 815 ms 13032 KB Output is correct
2 Correct 768 ms 8952 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1042 ms 13132 KB Output is correct
2 Correct 986 ms 9072 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1259 ms 12556 KB Output is correct
2 Correct 1145 ms 10108 KB Output is correct