#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 1000000001

int main(){
	
	vector<int> cnt(1000001,0);
	
	for(int i=2;i<cnt.size();i++){
		if(cnt[i]!=0)continue;
		for(int j=i;j<cnt.size();j+=i){
			int t = j;
			while(t%i==0){
				t /= i;
				cnt[j] ++;
			}
		}
	}
	
	int n;
	cin>>n;
	
	int x = 0;
	rep(i,n){
		int a;
		cin>>a;
		x ^= cnt[a];
	}
	//cout<<x<<endl;
	if(x==0)cout<<"black"<<endl;
	else cout<<"white"<<endl;
	
	return 0;
}