#include <bits/stdc++.h>

using i32 = std::int32_t;
using u32 = std::uint32_t;
using i64 = std::int64_t;
using u64 = std::uint64_t;
using i128 = __int128_t;
using u128 = __uint128_t;
using isize = std::ptrdiff_t;
using usize = std::size_t;

class rep {
    struct Iter {
        usize itr;
        constexpr Iter(const usize pos) noexcept : itr(pos) {}
        constexpr void operator++() noexcept { ++itr; }
        constexpr bool operator!=(const Iter& other) const noexcept { return itr != other.itr; }
        constexpr usize operator*() const noexcept { return itr; }
    };
    const Iter first, last;

  public:
    explicit constexpr rep(const usize first, const usize last) noexcept : first(first), last(std::max(first, last)) {}
    constexpr Iter begin() const noexcept { return first; }
    constexpr Iter end() const noexcept { return last; }
};

template <class T> usize compress(std::vector<T>& vec) {
    std::sort(vec.begin(), vec.end());
    vec.erase(std::unique(vec.begin(), vec.end()), vec.end());
    return vec.size();
}

template <class T> usize lowb(const std::vector<T>& vec, const T& val) {
    return std::distance(vec.cbegin(), std::lower_bound(vec.cbegin(), vec.cend(), val));
}

template <class T> usize upb(const std::vector<T>& vec, const T& val) {
    return std::distance(vec.cbegin(), std::upper_bound(vec.cbegin(), vec.cend(), val));
}

template <class T> using Vec = std::vector<T>;

void main_() {
    usize N;
    std::cin >> N;
    u32 ans = 0;
    Vec<u32> grundy(1000001);
    Vec<Vec<u32>> divs(1000001);
    for (const auto i : rep(1, 1000001)) {
        for (usize j = i + i; j <= 1000000; j += i) {
            divs[j].push_back(i);
        }
        Vec<u32> vec;
        for (const auto j : divs[i]) {
            vec.push_back(grundy[j]);
        }
        compress(vec);
        for (const auto x : vec) {
            if (grundy[i] == x) {
                grundy[i] += 1;
            } else {
                break;
            }
        }
    }
    while (N--) {
        u32 x;
        std::cin >> x;
        ans ^= grundy[x];
    }
    std::cout << (ans ? "white" : "black") << '\n';
}

int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin.tie(nullptr);
    main_();
    return 0;
}