#pragma region Macros // #pragma GCC target("avx2") #pragma GCC optimize("O3") #include #include #include #include using namespace std; using namespace __gnu_pbds; template using ordered_set = tree, rb_tree_tag, tree_order_statistics_node_update>; struct __INIT{__INIT(){cin.tie(0);ios::sync_with_stdio(false);cout<= 0; i--) #define ALL(v) v.begin(), v.end() #define endl "\n" #define fi first #define se second #define popcount(bit) __builtin_popcount(bit) #define popcountll(bit) __builtin_popcountll(bit) #define pb push_back #define eb emplace_back using namespace atcoder; using P = pair; using PL = pair; using Graph = vector>; typedef long long ll; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } const int dx[4] = {1, 0, -1, 0}; const int dy[4] = {0, 1, 0, -1}; const int fx[8] = {0, 1, 1, 1, 0, -1, -1, -1}; const int fy[8] = {1, 1, 0, -1, -1, -1, 0, 1}; template const auto INF = numeric_limits::max()/2; struct Sieve_prime{ vector f, primes; int n; Sieve_prime(int n = 1): n(n), f(n +1){ f[0] = f[1] = -1; for (ll i = 2; i <= n; i++){ if(f[i])continue; primes.emplace_back(i); f[i] = i; for (ll j = i * i; j <= n; j += i){ //この条件をつけると最小素因数が記録される //つけないと最大素因数が記録される。 if(!f[j]) f[j] = i; } } } bool isPrime(int x) { return f[x] == x; } vector factorlist(int x){ vector res; while (x != 1){ res.emplace_back(f[x]); x /= f[x]; } return res; } vector

factor(int x) { vector fl = factorlist(x); if (fl.size() == 0) return {}; vector

res(1, P(fl[0], 0)); for (int p : fl) { if (res.back().first == p) { res.back().second++; } else { res.emplace_back(p, 1); } } return res; } vector divisors(int x){ assert(x > 0); vector res = {1}; for(auto [p, e] : factor(x)){ int n = res.size() * e; for(int i=0; i> n; int x = 0; vector A(n); rep(i, n) cin >> A[i]; rep(i, n){ int c = 0; auto d = Sieve.factor(A[i]); for(auto [a, b] : d){ c += b; } x ^= c; } if(x){ cout << "white" << endl; }else{ cout << "black" << endl; } }