#pragma GCC optimize("Ofast") #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef long long int ll; typedef unsigned long long ull; mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count()); ll myRand(ll B) { return (ull)rng() % B; } int main(){ cin.tie(nullptr); ios::sync_with_stdio(false); int n; cin >> n; vector a(n); ll k=0; for(int i=0;i> a[i]; int sum = 0; for(int j=2;j*j<=a[i];j++){ while(a[i]%j==0){ sum++; a[i]/=j; } } if(a[i]>1)sum++; k^=sum; } if(k){ cout << "white" << endl; } else{ cout << "black" << endl; } }