#include <stdio.h>
#include <stdlib.h>

int main(void)
{
	int m,n, r, c;
	int* matrice;
	int* coloane;
	int* coloanes;
		
	int* idxranduri;
	
	long max = 0;

	freopen("elimin.in", "r", stdin);
	freopen("elimin.out", "w", stdout);

	scanf("%d %d %d %d", &m, &n, &r, &c);


	matrice = (int*)malloc(m*n*sizeof(int));

	int i;
	if(m<=n) 
	{
		for(i=0;i<m;++i)
		{
			for(int j=0;j<n;++j)
			{
				scanf("%d ", &matrice[n*i+j]);
			}
		}
	}
	else 
	{
		for(i=0;i<m;++i)
		{
			for(int j=0;j<n;++j)
			{
				scanf("%d ", &matrice[i+m*j]);
			}
		}

		int t = m;
		m = n;
		n = t;
		t = r;
		r = c;
		c = t;
	}

	coloane = (int*)malloc(n*sizeof(int));
	coloanes = (int*)malloc(n*sizeof(int));
	idxranduri = (int*)malloc((r+1)*sizeof(int));

	for(i=0;i<n;++i)
		coloane[i] = 0;

	for(i=0;i<m;++i)
	{
		for(int j=0;j<n;++j)
		{
			coloane[j] += matrice[n*i+j];
		}
	}

	int rand = 0;
	idxranduri[0] = 0;
	while(idxranduri[0] < m)
	{
		if(idxranduri[rand] < m)
		{
			++rand;
			idxranduri[rand] = idxranduri[rand-1]+1;
		}
		else
		{
			--rand;
			++idxranduri[rand];
		}

		if(rand >= r) 
		{
			for(i=0; i<n; ++i)
				coloanes[i] = coloane[i];
	
			for(i=0;i<r;++i)
			{
				for(int j=0;j<n;++j)
					coloanes[j] -= matrice[n*idxranduri[i]+j];
			}

			for(i=1;i<n;++i)
			{
				int a = coloanes[i];
				int poz = i-1;
				while(poz>=0 && coloanes[poz] > a)
				{
					coloanes[poz+1] = coloanes[poz];
					--poz;
				}
				coloanes[poz+1] = a;
			}

			int sum = 0;
			for(i=c;i<n;++i)
				sum += coloanes[i];

			if(sum > max)
				max = sum;

			--rand;
			++idxranduri[rand];
		}
		
	}

	printf("%ld\n", max);


	free(matrice);
	free(coloane);
	free(coloanes);
	free(idxranduri);

	return 0;
}