#pragma GCC optimize ("O3")
#include <bits/stdc++.h>

// clang-format off
using namespace std;
using ll = long long int;

#define all(v) (v).begin(),(v).end()
#define repeat(cnt,l) for(typename remove_const<typename remove_reference<decltype(l)>::type>::type cnt={};(cnt)<(l);++(cnt))
#define rrepeat(cnt,l) for(auto cnt=(l)-1;0<=(cnt);--(cnt))
#define iterate(cnt,b,e) for(auto cnt=(b);(cnt)!=(e);++(cnt))
#define increase(cnt,b,e) for(auto cnt=(b);(cnt)<(e);++(cnt))
#define decrease(cnt,b,e) for(auto cnt=(b);(e)<=(cnt);--(cnt))
const long long MD = 1000000007; const long double PI = 3.1415926535897932384626433832795L;
template<typename T1, typename T2> inline ostream& operator <<(ostream &o, const pair<T1, T2> p) { o << '(' << p.first << ':' << p.second << ')'; return o; }
template<typename T> inline T& chmax(T& to, const T& val) { return to = max(to, val); }
template<typename T> inline T& chmin(T& to, const T& val) { return to = min(to, val); }
void bye(string s, int code = 0) { cout << s << endl; exit(code); }
mt19937_64 randdev(8901016);
template<typename T, typename Random = decltype(randdev), typename enable_if<is_integral<T>::value>::type* = nullptr>
inline T rand(T l, T h, Random& rand = randdev) { return uniform_int_distribution<T>(l, h)(rand); }
template<typename T, typename Random = decltype(randdev), typename enable_if<is_floating_point<T>::value>::type* = nullptr>
inline T rand(T l, T h, Random& rand = randdev) { return uniform_real_distribution<T>(l, h)(rand); }template<typename T>
static ostream& operator<<(ostream& o, const std::vector<T>& v) {
  o << "[ "; for(const auto& e : v) o<<e<<' '; return o << ']';
}

template <typename I> struct MyRangeFormat{ I b,e; MyRangeFormat(I _b, I _e):b(_b),e(_e){} };
template<typename I> static ostream& operator<<(ostream& o, const MyRangeFormat<I>& f) {
  o << "[ "; iterate(i,f.b,f.e) o<<*i<<' '; return o << ']';
}
template <typename I> struct MyMatrixFormat{
  const I& p; long long n, m;
  MyMatrixFormat(const I& _p, long long _n, long long _m):p(_p),n(_n),m(_m){}
};
template<typename I> static ostream& operator<<(ostream& o, const MyMatrixFormat<I>& f) {
  o<<'\n';
  repeat(i,(f.n)) {
    repeat(j,f.m) o<<f.p[i][j]<<' ';
    o<<'\n';
  }
  return o;
}
struct LOG_t { ~LOG_t() { cout << endl; } };
#define LOG (LOG_t(),cout<<'L'<<__LINE__<<": ")
#define FMTA(m,w) (MyRangeFormat<decltype(m+0)>(m,m+w))
#define FMTR(b,e) (MyRangeFormat<decltype(e)>(b,e))
#define FMTV(v) FMTR(v.begin(),v.end())
#define FMTM(m,h,w) (MyMatrixFormat<decltype(m+0)>(m,h,w))

#if defined(_WIN32) || defined(_WIN64)
#define getc_x _getc_nolock
#define putc_x _putc_nolock
#elif defined(__GNUC__)
#define getc_x getc_unlocked
#define putc_x putc_unlocked
#else
#define getc_x getc
#define putc_x putc
#endif
class MaiScanner {
  FILE* fp_;
  constexpr bool isvisiblechar(char c) noexcept { return (0x21<=(c)&&(c)<=0x7E); }
public:
  inline MaiScanner(FILE* fp):fp_(fp){}
  template<typename T> void input_integer(T& var) noexcept {
    var = 0; T sign = 1;
    int cc = getc_x(fp_);
    for (; cc < '0' || '9' < cc; cc = getc_x(fp_))
      if (cc == '-') sign = -1;
    for (; '0' <= cc && cc <= '9'; cc = getc_x(fp_))
      var = (var << 3) + (var << 1) + cc - '0';
    var = var * sign;
  }
  inline int c() noexcept { return getc_x(fp_); }
  template<typename T, typename enable_if<is_integral<T>::value, nullptr_t>::type = nullptr>
  inline MaiScanner& operator>>(T& var) noexcept { input_integer<T>(var); return *this; }
  inline MaiScanner& operator>>(string& var) {
    int cc = getc_x(fp_);
    for (; !isvisiblechar(cc); cc = getc_x(fp_));
    for (; isvisiblechar(cc); cc = getc_x(fp_))
      var.push_back(cc);
    return *this;
  }
  template<typename IT> inline void in(IT begin, IT end) { for (auto it = begin; it != end; ++it) *this >> *it; }
};
class MaiPrinter {
  FILE* fp_;
public:
  inline MaiPrinter(FILE* fp):fp_(fp){}
  template<typename T>
  void output_integer(T var) noexcept {
    if (var == 0) { putc_x('0', fp_); return; }
    if (var < 0)
      putc_x('-', fp_),
      var = -var;
    char stack[32]; int stack_p = 0;
    while (var)
      stack[stack_p++] = '0' + (var % 10),
      var /= 10;
    while (stack_p)
      putc_x(stack[--stack_p], fp_);
  }
  inline MaiPrinter& operator<<(char c) noexcept { putc_x(c, fp_); return *this; }
  template<typename T, typename enable_if<is_integral<T>::value, nullptr_t>::type = nullptr>
  inline MaiPrinter& operator<<(T var) noexcept { output_integer<T>(var); return *this; }
  inline MaiPrinter& operator<<(char* str_p) noexcept { while (*str_p) putc_x(*(str_p++), fp_); return *this; }
  inline MaiPrinter& operator<<(const string& str) {
    const char* p = str.c_str();
    const char* l = p + str.size();
    while (p < l) putc_x(*p++, fp_);
    return *this;
  }
  template<typename IT> void join(IT begin, IT end, char sep = ' ') { for (bool b = 0; begin != end; ++begin, b = 1) b ? *this << sep << *begin : *this << *begin; }
};
MaiScanner scanner(stdin);
MaiPrinter printer(stdout);
// clang-format on

template <int Max = 2000>
class IsPrimeC {
  bool d_[Max + 1];

  template <typename T>
  static constexpr T cesqrt(T s) {
    double x = s / 2.0;
    double prev = 0.0;
    while (x != prev) {
      prev = x;
      x = (x + s / x) / 2.0;
    }
    return x;
  }

 public:
  constexpr IsPrimeC() : d_() {
    d_[0] = d_[1] = 1;
    int sqh = cesqrt<int>(Max);
    for (int i = 2; i <= sqh; i++) {
      if (d_[i] == 0) {
        for (int j = i * i; j <= Max; j += i) {  // i*i
          d_[j] = 1;
        }
      }
    }
    for (int i = 0; i <= Max; ++i)
      d_[i] = !d_[i];
  }
  constexpr inline bool operator[](int x) const { return d_[x]; }
};

template <int Max = 2000>
class PrimeListC {
  int d_[Max];

 public:
  constexpr PrimeListC() : d_() {
    int n = 1;
    d_[0] = 2;
    for (int x = 3; n < Max; ++x) {
      bool f = true;
      for (int i = 0; d_[i] * d_[i] <= x; ++i)
        if (x / d_[i] * d_[i] == x) {
          f = false;
          break;
        }
      if (f)
        d_[n++] = x;
    }
  }
  constexpr inline int operator[](int x) const { return d_[x]; }
  template <int _Max>
  class iterator {
    const PrimeListC<_Max>& pl;
    int ptr = 0;

   public:
    constexpr iterator(const decltype(pl)& _pl, int _ptr = 0) : pl(_pl), ptr(_ptr) {}
    constexpr int operator*() const { return pl[ptr]; }
    constexpr iterator<_Max>& operator++() {
      ptr++;
      return *this;
    }  // prefix
    constexpr inline bool operator!=(const iterator<_Max>& it) const {
      return ptr != it.ptr ? !(_Max < ptr && _Max < it.ptr) : false;
    }
    constexpr inline bool operator==(const iterator<_Max>& it) const {
      return ptr != it.ptr ? (_Max < ptr && _Max < it.ptr) : true;
    }
  };
  constexpr PrimeListC::iterator<Max> begin() const { return PrimeListC::iterator<Max>(*this, 0); }
  constexpr PrimeListC::iterator<Max> end() const { return PrimeListC::iterator<Max>(*this, Max); }

  std::map<long long, int> division(long long number) const {
    std::map<long long, int> div;
    for (int i = 0; number > 1 && i < Max; ++i) {
      long long p = d_[i];
      int c = 0;
      while (number / p * p == number)
        ++c, number /= p;
      if (c > 0)
        div[p] = c;
    }
    return div;
  }
};

//

PrimeListC<100001> prime;

//


int main() {
  int N;
  scanner >> N;
  int x = 0;
  repeat(i, N) {
    int a; scanner >> a;
    auto m = prime.division(a);
    for (auto p : m)
      x ^= p.second;
  }
  cout << (x ? "white" : "black") << endl;
  
  return 0;
}