/*
   Keep It Simple!
*/

#include <stdio.h>

#define MaxN 5005

int N,K,A,B;
int v[MaxN];
long long Sol,S;

int main()
{
	freopen("divk.in","r",stdin);
	freopen("divk.out","w",stdout);

	scanf("%d%d%d%d",&N,&K,&A,&B);

	for(int i=1; i<=N; i++)
		scanf("%d",&v[i]);

	for(int i=1; i<=N; i++)
	{
		S = v[i];
		for(int j=i+1; j<=i+B && j<=N; j++)
		{
			S = S + v[j];
			if( S%K==0 )
				Sol++;
		}
	}		

	printf("%lld",Sol);
}