oj.uz

Submission #52625

# Submission time Handle Problem Language Result Execution time Memory
52625 2018-06-26T09:56:01 Z Alexa2001 Pipes (CEOI15_pipes) C++17
100 / 100
 1213 ms 14044 KB 
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
const int Nmax = 1e5 + 5;

int n, m, i, x, y;
int level[Nmax], low[Nmax];
vector<int> v[Nmax];

struct Forest
{
    int t[Nmax];

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

    int boss(int x)
    {
        if(t[x] == x) return x;
        return t[x] = boss(t[x]);
    }

    void unite(int x, int y)
    {
        x = boss(x), y = boss(y);
        t[x] = y;
    }
} A, B;

void solve(int node, int dad = 0)
{
    level[node] = low[node] = level[dad] + 1;

    bool ok = 0;
    for(auto son : v[node])
    {
        if(son == dad && !ok)
        {
            ok = 1;
            continue;
        }

        if(level[son])
        {
            low[node] = min(low[node], level[son]);
            continue;
        }

        solve(son, node);
        low[node] = min(low[node], low[son]);

        if(low[son] == level[son])
            cout << node << ' ' << son << '\n';
    }
}

int main()
{
  //  freopen("input", "r", stdin);
  //  freopen("output", "w", stdout);
    cin.sync_with_stdio(false);

    cin >> n >> m;
    A.clear(); B.clear();

    while(m--)
    {
        cin >> x >> y;
        if(B.boss(x) == B.boss(y)) continue; /// same bcomp

        if(A.boss(x) != A.boss(y)) A.unite(x, y);
            else B.unite(x, y);

        v[x].push_back(y);
        v[y].push_back(x);
    }

    for(i=1; i<=n; ++i)
        if(!level[i]) solve(i);

    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3 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 8 ms 3172 KB Output is correct
2 Correct 8 ms 3044 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 99 ms 3040 KB Output is correct
2 Correct 102 ms 2908 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 168 ms 3832 KB Output is correct
2 Correct 204 ms 3320 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 286 ms 5340 KB Output is correct
2 Correct 243 ms 4960 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 426 ms 10600 KB Output is correct
2 Correct 358 ms 7164 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 645 ms 11876 KB Output is correct
2 Correct 596 ms 9020 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 833 ms 14044 KB Output is correct
2 Correct 780 ms 9084 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1038 ms 14040 KB Output is correct
2 Correct 930 ms 9208 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1213 ms 13456 KB Output is correct
2 Correct 1113 ms 10508 KB Output is correct