graph-1

#include <iostream>

void dfsUtil(vector<int> g[], int v, bool visited[], vector<int>&res){
    if(!visited[v]){
        visited[v]=true;
        res.push_back(v);
        for(int i=0;i<g[v].size();++i){   
            dfsUtil(g,g[v][i],visited,res);
        }
    }
}

vector <int> dfs(vector<int> g[], int N)
{
    bool visited[N]={false};
    vector <int>res;
    if(N==0)
    return res;
    dfsUtil(g,0,visited,res);
    return res;
}

vector <int> bfs(vector<int> g[], int N) {
    std::vector<int>res;
    if(N==0)
    return res;
    
    std::queue<int>q;
    bool visited[N]={false};
    q.push(0);
    while(!q.empty()){
        int v = q.front();
        if(!visited[v]){
            visited[v]=true;
            res.push_back(v);
            for(int i=0;i<g[v].size();++i){
                if(!visited[g[v][i]])
                q.push(g[v][i]);
            }
            q.pop();
        }
    }
    return res;
}

bool isCyclicUtil(vector<int>g[],int v,bool visited[],bool rec[]){
    if(!visited[v]){
        visited[v]=true;
        rec[v]=true;
        for(int i=0;i<g[v].size();++i){
            if(!visited[g[v][i]]){
              if(isCyclicUtil(g,g[v][i],visited,rec))
                return true;
            }else if(rec[g[v][i]])
            return true;
        }
    }
    rec[v]=false;
    return false;
}

bool isCyclic(int V, vector<int> adj[])
{
  bool visited[V]={false};
  bool rec[V]={false};
  for(int i=0;i<V;++i){
      if(!visited[i]){
           if(isCyclicUtil(adj,i,visited,rec))
           return true;
      }
  }
  return false;
}

bool isCyclicUtilUND(vector<int>g[],int v,bool visited[],int parent){
    visited[v]=true;
    //std::cout<<v<<" "<<parent<<"\n";
    for(int i=0;i<g[v].size();++i){
        if(!visited[g[v][i]]){
          if(isCyclicUtilUND(g,g[v][i],visited,v))
          return true;
        }else if(g[v][i]!=parent)
            return true;
    }
    return false;
}

bool isCyclicUND(vector<int> g[], int V)
{
  bool visited[V]={false};
  for(int i=0;i<V;++i){
      if(!visited[i]){
          if(isCyclicUtilUND(g,i,visited,-1))
            return true;
      }
  }
  return false;
}

int main()
{
    cout<<"Hello World";

    return 0;
}