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Submission #804601

# Submission time Handle Problem Language Result Execution time Memory
804601 2023-08-03T10:08:33 Z Hanksburger Pipes (CEOI15_pipes) C++17
100 / 100
 2417 ms 14308 KB 
#include <bits/stdc++.h>
using namespace std;
vector<int> adj[100005];
int par[100005][2], t;
int findPar(int u, int x)
{
    return (par[u][x]==u?u:par[u][x]=findPar(par[u][x], x));
}
void dfs(int u, int p)
{
    par[u][0]=par[u][1]=(++t);
    int pass=1;
    for (int v:adj[u])
    {
        if (v==p && pass)
        {
            pass=0;
            continue;
        }
        if (par[v][0])
            par[u][1]=min(par[u][1], par[v][0]);
        else
        {
            dfs(v, u);
            par[u][1]=min(par[u][1], par[v][1]);
            if (par[v][1]>=par[v][0])
                cout << u << ' ' << v << '\n';
        }
    }
}
int main()
{
    int n, m;
    cin >> n >> m;
    for (int i=1; i<=n; i++)
        par[i][0]=par[i][1]=i;
    for (int i=1; i<=m; i++)
    {
        int u, v, U, V;
        cin >> u >> v;
        if (findPar(u, 0)!=findPar(v, 0))
        {
            par[par[u][0]][0]=par[v][0];
            adj[u].push_back(v);
            adj[v].push_back(u);
        }
        else if (findPar(u, 1)!=findPar(v, 1))
        {
            par[par[u][1]][1]=par[v][1];
            adj[u].push_back(v);
            adj[v].push_back(u);
        }
    }
    for (int i=1; i<=n; i++)
        par[i][0]=par[i][1]=0;
    for (int i=1; i<=n; i++)
        if (!par[i][0])
            dfs(i, 0);
}

Compilation message

pipes.cpp: In function 'int main()':
pipes.cpp:39:19: warning: unused variable 'U' [-Wunused-variable]
   39 |         int u, v, U, V;
      |                   ^
pipes.cpp:39:22: warning: unused variable 'V' [-Wunused-variable]
   39 |         int u, v, U, V;
      |                      ^

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2656 KB Output is correct
2 Correct 2 ms 2656 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 3252 KB Output is correct
2 Correct 8 ms 2928 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 246 ms 3332 KB Output is correct
2 Correct 216 ms 3176 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 366 ms 4132 KB Output is correct
2 Correct 432 ms 3476 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 585 ms 5700 KB Output is correct
2 Correct 530 ms 5124 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 794 ms 10636 KB Output is correct
2 Correct 634 ms 6652 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1143 ms 12128 KB Output is correct
2 Correct 1163 ms 8604 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1514 ms 14164 KB Output is correct
2 Correct 1433 ms 8604 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1959 ms 14308 KB Output is correct
2 Correct 1809 ms 8524 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2417 ms 13776 KB Output is correct
2 Correct 2379 ms 10640 KB Output is correct