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Submission #56540

# Submission time Handle Problem Language Result Execution time Memory
56540 2018-07-11T15:11:51 Z admin Pipes (CEOI15_pipes) C++14
100 / 100
 1253 ms 13964 KB 
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
const int MX=100010, inf=2e9;
 
 
int n, m;
int U[2][MX];
 
vector<int> G[MX];
 
int find(int t, int x){
    return x==U[t][x] ? x : U[t][x]=find(t,U[t][x]);
}
void unite(int t, int x, int y){
    if(find(t,x)==find(t,y)) return;
    U[t][U[t][y]]=U[t][x];
}
 
int up[MX], dep[MX], now;
void dfs(int v, int p){
    dep[v]=++now; up[v]=dep[v];
    bool multi=false;
    for(int x:G[v]){
        if(x==p){
            if(multi) up[v]=min(up[v], dep[p]);
            multi=true;
            continue;
        }
        if(dep[x]>0) up[v]=min(up[v], dep[x]);
        else{
            dfs(x,v);
            up[v]=min(up[v], up[x]);
            if(up[x]>dep[v]) cout<<v<<' '<<x<<'\n';
        }
    }
    now--;
}
 
int main(){
    ios::sync_with_stdio(0); cin.tie(0);
    cin>>n>>m;
    for(int i=1; i<=n; i++) U[0][i]=U[1][i]=i;
    for(int i=1; i<=m; i++){
        int u, v; cin>>u>>v;
        if(find(0,u)==find(0,v)){
            if(find(1,u)==find(1,v)) continue;
            unite(1,u,v);
        }
        else unite(0,u,v);
        G[u].push_back(v);
        G[v].push_back(u);
    }
    for(int i=1; i<=n; i++)
        if(dep[i]==0) dfs(i,-1);
    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2688 KB Output is correct
2 Correct 3 ms 2688 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 3200 KB Output is correct
2 Correct 7 ms 2944 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 98 ms 3044 KB Output is correct
2 Correct 97 ms 2904 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 158 ms 3724 KB Output is correct
2 Correct 190 ms 3304 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 283 ms 5424 KB Output is correct
2 Correct 252 ms 4984 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 419 ms 10604 KB Output is correct
2 Correct 365 ms 7160 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 625 ms 11864 KB Output is correct
2 Correct 614 ms 8952 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 876 ms 13916 KB Output is correct
2 Correct 772 ms 9076 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1062 ms 13964 KB Output is correct
2 Correct 955 ms 9076 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1239 ms 13392 KB Output is correct
2 Correct 1253 ms 10592 KB Output is correct