#include <iostream>
using namespace std;
 
const int MAX_SIZE = 20;
 
int main() {
	int n, m , x, y, mt[MAX_SIZE + 1][MAX_SIZE + 1];
	cin >> n >> m >> x >> y;
	for (int i = 1; i <= n; ++i) {
		for (int j = 1; j <= m; ++j) {
			cin >> mt[i][j];
		}
	}
	int counterSteps = 0, xSteps = x, ySteps = y;
	int copyN = n, copyM = m;
	while (copyN > 1 || copyM > 1) {
		if (copyN - xSteps >= 1 && xSteps > 0 ) {
			copyN -= xSteps;
			++counterSteps; 
		}
		if (copyM - ySteps >= 1 &&ySteps > 0) {
			copyM -= ySteps; 
			++counterSteps;
		}
		if (copyN - xSteps < 1 && copyN >= 1) {
			--xSteps;
		}
		if (copyM - ySteps < 1 && copyM >= 1) {
			--ySteps;
		}
	}
	cout << counterSteps;
	return 0;
}

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3 1 
4 5 
4 5 
4 5 
4 5 
4 5 
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4 5