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Submission #703047

# Submission time Handle Problem Language Result Execution time Memory
703047 2023-02-25T19:04:29 Z amirhoseinfar1385 Potemkin cycle (CEOI15_indcyc) C++17
100 / 100
 314 ms 6292 KB 
#include<bits/stdc++.h>
using namespace std;
const int maxn=1000+5;
int n,m;
vector<int>adj[maxn],fake[maxn];
vector<int>bf;
int par[maxn];
int mat[maxn][maxn],vis[maxn],visd[maxn],visb[maxn];
vector<int>allv[maxn];
int now=0;

void dfs(int u){
    if(visd[u]==1){
        return ;
    }
    visd[u]=1;
    if(vis[u]==1){
        allv[now].push_back(u);
        return ;
    }
    for(auto x:adj[u]){
        dfs(x);
    }
}

void bfs(int had){
    for(auto x:bf){
        if(x==had){
            while(x>0){
                cout<<x<<" ";
                x=par[x];
            }
            return ;
        }
        visb[x]=1;
    }
    //cout<<"salam"<<endl;
    vector<int>fakebf;
    for(auto x:bf){
        for(auto y:fake[x]){
            if(visb[y]==0){
                visb[y]=1;
                par[y]=x;
                fakebf.push_back(y);
                //cout<<y<<endl;
            }
        }
    }
   // cout<<(int)fakebf.size()<<endl;
    swap(fakebf,bf);
    return bfs(had);
}

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin>>n>>m;
    for(int i=0;i<m;i++){
        int u,v;
        cin>>u>>v;
        adj[u].push_back(v);
        adj[v].push_back(u);
        mat[u][v]=1;
        mat[v][u]=1;
    }
    for(int u=1;u<=n;u++){
        for(int i=0;i<maxn;i++){
            vis[i]=visd[i]=0;
            allv[i].clear();
        }
        vis[u]=1;
        for(auto x:adj[u]){
            vis[x]=1;
        }
        for(int j=1;j<=n;j++){
            now=j;
            dfs(j);
        }
        for(int j=1;j<=n;j++){
            allv[j].resize(unique(allv[j].begin(),allv[j].end())-allv[j].begin());
        }
        for(int v=1;v<=n;v++){
            for(int i=0;i<(int)allv[v].size();i++){
                for(int j=i+1;j<(int)allv[v].size();j++){
                    if(mat[allv[v][i]][allv[v][j]]==0){
                        for(int h=0;h<=n;h++){
                            if(vis[h]==1&&(h!=allv[v][i]&&allv[v][j]!=h)){
                                continue;
                            }
                         //   cout<<"asd "<<h<<endl;
                            for(auto x:adj[h]){
                                if(vis[x]==1&&(x!=allv[v][i]&&x!=allv[v][j])){
                                    continue;
                                }
                                fake[h].push_back(x);
                             //   cout<<h<<" "<<x<<endl;
                            }
                        }
                     //   cout<<allv[v][i]<<" "<<allv[v][j]<<" "<<u<<endl;
                        bf.push_back(allv[v][i]);
                        bfs(allv[v][j]);
                        cout<<u<<"\n";
                        return 0;
                    }
                }   
            }
        }
    }
    cout<<"no\n";
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 404 KB Output is correct
3 Correct 1 ms 396 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 392 KB Output is correct
2 Correct 1 ms 340 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 724 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 784 KB Output is correct
2 Correct 1 ms 724 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 1568 KB Output is correct
2 Correct 2 ms 1620 KB Output is correct
3 Correct 2 ms 1748 KB Output is correct
4 Correct 12 ms 1688 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1620 KB Output is correct
2 Correct 8 ms 1620 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 5716 KB Output is correct
2 Correct 16 ms 5024 KB Output is correct
3 Correct 289 ms 5280 KB Output is correct
4 Correct 139 ms 4836 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 29 ms 4812 KB Output is correct
2 Correct 130 ms 4692 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 3832 KB Output is correct
2 Correct 19 ms 3916 KB Output is correct
3 Correct 22 ms 6292 KB Output is correct
4 Correct 314 ms 5728 KB Output is correct