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Submission #54938

# Submission time Handle Problem Language Result Execution time Memory
54938 2018-07-05T13:37:51 Z Diuven Pipes (CEOI15_pipes) C++11
100 / 100
 1523 ms 14072 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 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 3200 KB Output is correct
2 Correct 8 ms 2944 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 101 ms 3056 KB Output is correct
2 Correct 97 ms 2944 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 162 ms 3728 KB Output is correct
2 Correct 192 ms 3292 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 290 ms 5408 KB Output is correct
2 Correct 264 ms 5024 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 438 ms 10688 KB Output is correct
2 Correct 380 ms 7160 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 671 ms 11852 KB Output is correct
2 Correct 650 ms 9236 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 875 ms 14072 KB Output is correct
2 Correct 835 ms 9080 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1033 ms 14052 KB Output is correct
2 Correct 968 ms 9080 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1523 ms 13428 KB Output is correct
2 Correct 1232 ms 10588 KB Output is correct