#include <stdio.h>
long a,b,n,k,l,nu,nr;
long v[500001];
long long max=0;
int main ()
{
 long i,j;
 FILE *f=fopen("divk.in","r");
 FILE *g=fopen("divk.out","w");

 fscanf(f,"%d%d%d%d",&n,&k,&a,&b);
 for(i=1;i<=n;i++)
  {
   fscanf(f,"%d",&v[i]);
  }
 for(i=1;i<a;i++)
  nu=nu+v[i];
 for(i=a;i<=n;i++)
  {
   nu=nu+v[i];
   nr=nu;
   if(nr%k==0)
    max++;
   for(j=i-a;j>=1&&j>i-b;j--)
    {
     nr=nr+v[j];
     if(nr%k==0)
      max++;
    }
   nu=nu-v[i-a+1];
  }

 fprintf(g,"%d",max);
 return 0;
}