#include<stdio.h>
#include<string.h>

#define X 500001

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

    int v[X],sum[X],n,k,a,b,i,j,l,u,cnt=0;

    memset(sum,0,sizeof(sum));
    scanf("%d %d %d %d",&n, &k, &a, &b);

    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,l=1; j<=n && l<=b-a+1; ++j,++l)
	if((sum[j]-sum[i-1])%k==0) ++cnt;

    printf("%d\n",cnt);

    return 0;
}