#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long int ll;
typedef long double ld;
#define FOR(i,l,r) for(ll i=l;i<r;i++)
#define REP(i,n) FOR(i,0,n)
#define RFOR(i,l,r) for(ll i=r-1;i>=l;i--)
#define RREP(i,n) RFOR(i,0,n)
#define ALL(x) x.begin(),x.end()
#define P pair<ll,ll>
#define F first
#define S second
#define BS(A,x) binary_search(ALL(A),x)
#define LB(A,x) (ll)(lower_bound(ALL(A),x)-A.begin())
#define UB(A,x) (ll)(upper_bound(ALL(A),x)-A.begin())
#define COU(A,x) UB(A,x)-LB(A,x)
template<typename T>using min_priority_queue=priority_queue<T,vector<T>,greater<T>>;
using mint=modint1000000007;
signed main(){
  ll N,ans=0;cin>>N;vector<ll>D(1000000);
  REP(i,1000000){
    ll x=i+1,d=2;while(d*d<=x){while(x%d==0){D[i]++;x/=d;}d++;}if(x>1)D[i]++;
  }
  REP(i,N){ll x;cin>>x;ans^=D[x-1];}
  if(ans)cout<<"white"<<endl;else cout<<"black"<<endl;
  return 0;
}