#include <bits/stdc++.h>

using namespace std;

typedef long long int ll;
typedef double ld;

typedef pair<ll, ll> ii;
typedef vector<ll> vi;
typedef vector<ii> vii;

#define PB push_back
#define ff first
#define ss second

#define FOR(prom,a,b) for ( ll prom = (a); prom < (ll)(b); ++prom)
#define F(a) FOR(i,0,a)
#define FF(a) FOR(j,0,a)

//#define M_PI 3.14159265358979323846
#define EPS (1e-10)
#define EQ(a,b) (fabs(a-b) <= fabs(a+b)*EPS)
#define LINF (1<<62LL)
#define DEB cerr<<"DEB: "

#define MX 0


int main() {
	ios::sync_with_stdio(false);
	ll xx,yy,x,y;
	cin >> x >> y >> xx >> yy;
	if((xx%2==yy%2&&x%2==y%2)||(xx%2!=yy%2&&x%2!=y%2))
		cout << "black" << endl;
	else
		cout << "white" << endl;
	return 0;
}