#include<stdio.h>
#define N 500100
int main(){
	int v[N],n,k,a,b,i,j,y=0,sum[N];
	freopen("divk.in","r",stdin);
	freopen("divk.out","w",stdout);
	scanf("%d%d%d%d",&n,&k,&a,&b);
	sum[0]=0;
	for (i=1;i<=n;++i){
		scanf("%d",&v[i]);
		sum[i]=sum[i-1]+v[i];
	}
	for (i=1;i<=n-a+1;++i)
		for (j=i+a-1;j<=i+b-1 && j<=n;++j)
			if ((sum[j]-sum[i-1])%k == 0)
				++y;
	printf("%d\n",y);
	return 0;
}