#ifdef LOCAL
//#define _GLIBCXX_DEBUG
#endif
//#pragma GCC target("avx512f,avx512dq,avx512cd,avx512bw,avx512vl")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> P;
typedef pair<int, int> Pi;
typedef vector<ll> Vec;
typedef vector<int> Vi;
typedef vector<string> Vs;
typedef vector<char> Vc;
typedef vector<P> VP;
typedef vector<vector<ll>> VV;
typedef vector<vector<int>> VVi;
typedef vector<vector<char>> VVc;
typedef vector<vector<vector<ll>>> VVV;
typedef vector<vector<vector<vector<ll>>>> VVVV;

#define endl '\n'
#define REP(i, a, b) for(ll i=(a); i<(b); i++)
#define PER(i, a, b) for(ll i=(a); i>=(b); i--)
#define rep(i, n) REP(i, 0, n)
#define per(i, n) PER(i, n, 0)
const ll INF=1e18+18;
const ll MOD=1000000007;
#define Yes(n) cout << ((n) ? "Yes" : "No") << endl;
#define YES(n) cout << ((n) ? "YES" : "NO") << endl;
#define ALL(v) v.begin(), v.end()
#define rALL(v) v.rbegin(), v.rend()
#define pb(x) push_back(x)
#define mp(a, b) make_pair(a,b)
#define Each(a,b) for(auto &a :b)
#define rEach(i, mp) for (auto i = mp.rbegin(); i != mp.rend(); ++i)
#ifdef LOCAL
#define dbg(x_) cerr << #x_ << ":" << x_ << endl;
#define dbgmap(mp) cerr << #mp << ":"<<endl; for (auto i = mp.begin(); i != mp.end(); ++i) { cerr << i->first <<":"<<i->second << endl;}
#define dbgset(st) cerr << #st << ":"<<endl; for (auto i = st.begin(); i != st.end(); ++i) { cerr << *i <<" ";}cerr<<endl;
#define dbgarr(n,m,arr) rep(i,n){rep(j,m){cerr<<arr[i][j]<<" ";}cerr<<endl;}
#define dbgdp(n,arr) rep(i,n){cerr<<arr[i]<<" ";}cerr<<endl;
#else
#define dbg(...)
#define dbgmap(...)
#define dbgset(...)
#define dbgarr(...)
#define dbgdp(...)
#endif
#define out(a) cout<<a<<endl
#define out2(a,b) cout<<a<<" "<<b<<endl
#define vout(v) rep(i,v.size()){cout<<v[i]<<" ";}cout<<endl
#define Uniq(v) v.erase(unique(v.begin(), v.end()), v.end())
#define fi first
#define se second

template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return true; } return false; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return true; } return false; }

template<typename T1, typename T2>
ostream &operator<<(ostream &s, const pair<T1, T2> &p) { return s<<"("<<p.first<<", "<<p.second<<")"; }

template<typename T>istream& operator>>(istream&i,vector<T>&v)
{rep(j,v.size())i>>v[j];return i;}

// vector
template<typename T>
ostream &operator<<(ostream &s, const vector<T> &v) {
    int len=v.size();
    for(int i=0; i<len; ++i) {
        s<<v[i];
        if(i<len-1) s<<"	";
    }
    return s;
}

// 2 dimentional vector
template<typename T>
ostream &operator<<(ostream &s, const vector<vector<T> > &vv) {
    s<<endl;
    int len=vv.size();
    for(int i=0; i<len; ++i) {
        s<<vv[i]<<endl;
    }
    return s;
}

vector<ll> divisor(ll n) {
    vector<ll> ret;
    for(ll i=1; i*i<=n; i++) {
        if(n%i==0) {
            ret.pb(i);
            if(i*i!=n) {
                ret.pb(n/i);
            }
        }
    }
    return ret;
}

vector<pair<ll,ll>> factorize(ll n) {
    vector<pair<ll,ll>> res;
    for (ll i = 2; i*i <= n; ++i) {
        if (n%i) continue;
        res.emplace_back(i,0);
        while (n%i == 0) {
            n /= i;
            res.back().second++;
        }
    }
    if (n != 1) res.emplace_back(n,1);
    return res;
}

vector< bool > prime_table(int n) {
    vector< bool > prime(n + 1, true);
    if(n >= 0) prime[0] = false;
    if(n >= 1) prime[1] = false;
    for(int i = 2; i * i <= n; i++) {
        if(!prime[i]) continue;
        for(int j = i + i; j <= n; j += i) {
            prime[j] = false;
        }
    }
    return prime;
}

int solve(){
    ll n;
    cin>>n;
    Vec a(n);
    cin>>a;
    Vec x(n);

    ll mx = 1e6+10;
    Vec C(mx);
    vector<bool> pt = prime_table(mx);
    Vec primes;
    rep(i,mx){
        if(pt[i])primes.push_back(i);
    }
    Each(p, primes){
        ll val = p;
        REP(_, 0, 30){
            val *= p;
            if(val < mx){
                primes.pb(val);
            }else{
                break;
            }
        }
    }

    Each(x, primes){
        for(ll y = x; y < mx; y += x){
            C[y] += 1;
        }
    }

    dbgdp(20, C);
    rep(i, n){
//        VP fact = factorize(a[i]);
//        ll cnt = 0;
//        Each(p, fact){
//            cnt += p.se;
//        }
        x[i] = C[a[i]];
    }
    ll sum = 0;
    rep(i,n){
        sum ^= x[i];
    }
    if(sum!=0){
        cout<<"white"<<endl;
    }else{
        cout<<"black"<<endl;
    }
    return  0;
}

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout<<std::setprecision(10);
//    ll T;
//    cin>>T;
//    while(T--)
    solve();
}