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

#define all(a) (a).begin(), (a).end()
using ll = long long;
using ull = unsigned long long;
using vll = vector<ll>;
ull bit(int n) { return 1ull << n; }
ll sign(ll a) { return (a > 0) - (a < 0); }
ll fdiv(ll a, ll b) { return a / b - ((a ^ b) < 0 && a % b); }
ll cdiv(ll a, ll b) { return -fdiv(-a, b); }
template <typename T> using priority_queue_rev = priority_queue<T, vector<T>, greater<T>>;
template <typename T> T sq(const T &a) { return a * a; }
template <typename T, typename U> bool chmax(T &a, const U &b) { return ((a < b) ? (a = b, true) : (false)); }
template <typename T, typename U> bool chmin(T &a, const U &b) { return ((a > b) ? (a = b, true) : (false)); }
template <typename T> ostream &operator<<(ostream &os, const vector<T> &a) {
    os << "(";
    for (auto itr = a.begin(); itr != a.end(); itr++) { os << *itr << (next(itr) != a.end() ? ", " : ""); }
    os << ")";
    return os;
}

#ifdef ONLINE_JUDGE
#define dump(...) (void(0))
#else
void debug() { cerr << endl; }
template <typename Head, typename... Tail> void debug(Head &&head, Tail &&... tail) {
    cerr << head;
    if (sizeof...(Tail)) cerr << ", ";
    debug(tail...);
}
#define dump(...) cerr << __LINE__ << ": " << #__VA_ARGS__ << " = ", debug(__VA_ARGS__)
#endif

struct rep {
    struct itr {
        int v;
        itr(int v) : v(v) {}
        void operator++() { ++v; }
        int operator*() const { return v; }
        bool operator!=(const itr &i) const { return v != i.v; }
    };
    int l, r;
    rep(int r) : l(min(0, r)), r(r) {}
    rep(int l, int r) : l(min(l, r)), r(r) {}
    itr begin() const { return l; };
    itr end() const { return r; };
};
struct per {
    struct itr {
        int v;
        itr(int v) : v(v) {}
        void operator++() { --v; }
        int operator*() const { return v; }
        bool operator!=(const itr &i) const { return v != i.v; }
    };
    int l, r;
    per(int r) : l(min(0, r)), r(r) {}
    per(int l, int r) : l(min(l, r)), r(r) {}
    itr begin() const { return r - 1; };
    itr end() const { return l - 1; };
};

template <typename F> ll binary_search(ll ok, ll ng, F is_ok) {
    while (abs(ok - ng) > 1) {
        ll mid = (ok + ng) / 2;
        (is_ok(mid) ? ok : ng) = mid;
    }
    return ok;
}

struct multi_prime_factorize {
    std::vector<int> spf;
    multi_prime_factorize(int n) : spf(n + 1) {
        std::iota(spf.begin(), spf.end(), 0LL);
        for (int i = 2; i * i <= n; i++) {
            if (spf[i] < i) { continue; }
            for (int j = i * i; j <= n; j += i) {
                if (spf[j] == j) { spf[j] = i; }
            }
        }
    }
    std::vector<int> prime_factorize(int a) {
        std::vector<int> ret;
        while (a > 1) {
            ret.emplace_back(spf[a]);
            a /= spf[a];
        }
        return ret;
    }
};

int main() {
    ll n;
    cin >> n;
    vll a(n);
    multi_prime_factorize mpf(1e6);
    ll g = 0;
    for (ll i : rep(n)) {
        cin >> a[i];
        g ^= mpf.prime_factorize(a[i]).size();
    }
    if (g == 0) {
        cout << "black" << endl;
    } else {
        cout << "white" << endl;
    }
}