BFS Basic, C++ (gcc)

Language: Layout:

//g++  7.4.0

#include<bits/stdc++.h>
using namespace std;
const int N = 100000;
vector<int> adj[N];
//map<int , vector<int>> adj;
bool bidir = true;
vector<bool> visited(N , false);

void bfs(int v)
{
    //cout<<v<<" ";
    visited[v] = true;
    queue<int> q;
    q.push(v);
    while(! q.empty())
    {   int node = q.front();
        q.pop();
        cout<<node<<" ";
        for( int x : adj[node])
        {if( visited[x] == true)
             continue;
            q.push(x);
            visited[x] = true;
        }
    }
}

void addEdge(int x , int y)
{
    adj[x].push_back(y);
        if(bidir)
            adj[y].push_back(x);
}
void printGraph(int v)
{
    for(int i=1 ; i<=v ;i++)
    {   cout<<"node "<<i<<" ";
        for(int x : adj[i])
            cout<<x<<" ";
        cout<<endl;
    }
}
int main()
{
   int v,e;
    
    cin>>v>>e;
    //create graph in adj list
    for(int i=0 ;i<e ;i++)
    {
        int x,y;
        cin>>x>>y;
        addEdge(x,y);
        
        
    }
    //print graph in adj list
    printGraph(v);
    
    bfs(1);
    
    return 0;
        
}

Show compiler warnings [ + ] Compiler args [ - ] Show input
Compilation time: 1.32 sec, absolute running time: 0.15 sec, cpu time: 0.01 sec, memory peak: 5 Mb, absolute service time: 1,51 sec