Bicoloring

#include<bits/stdc++.h>
using namespace std;

#define dk23      ios_base :: sync_with_stdio(false);
#define pb        push_back

int node,edge,n1,n2;
vector <int> v[205];
bool vis[205];
int color[205];

bool bfs()
{
    queue <int> q;
    q.push(0);
    vis[0]=true;
    color[0]=2;
    while(!q.empty())
    {
        int x = q.front();
        q.pop();
        for(int i=0;i<v[x].size();i++){
            int y=v[x][i];
            if(!vis[y]){
                vis[y]=true;
                q.push(y);
                if(color[x]==2){
                    color[y]=3;
                }
                else{
                    color[y]=2;
                }
            }
            else{
                if(color[x]==color[y]){
                    return false;
                }
            }
        }
    }
    return true;
}


int main()
{
    dk23

    //freopen("input.txt","r",stdin);

    while(cin>>node && node!=0)
    {
        cin>>edge;

        for(int i=0;i<edge;i++) {
            cin>>n1>>n2;
            v[n1].pb(n2);
            v[n2].pb(n1);
        }
        if(bfs()){
            cout<<"BICOLORABLE."<<endl;
        }
        else {
            cout<<"NOT BICOLORABLE."<<endl;
        }

        for(int i=0;i<node;i++){
            v[i].clear();
        }
        memset(vis,0,sizeof(vis));
        memset(color,0,sizeof(color));
    }
    return 0;
}