#include <iostream>
#include <cstdio>

using namespace std;

int main()
{
	int whiteX, whiteY, blackX, blackY;
	
	cin >> whiteX;
	cin >> whiteY;
	cin >> blackX;
	cin >> blackY;
	
	bool whiteOnBlack = (whiteX % 2 == 0 && whiteY % 2 == 0) || ((whiteX % 2 == 1 && whiteY % 2 == 1));
	bool blackOnBlack = (blackX % 2 == 0 && blackY % 2 == 0) || ((blackX % 2 == 1 && blackY % 2 == 1));
	
	if((whiteOnBlack && blackOnBlack) || (!whiteOnBlack && !blackOnBlack))
		cout << "black" << endl;
	else
		cout << "white" << endl;
	
	




	return 0;
}