/*
 *
 *
  info-arena 2.0 - Arhiva - Divk
 *
 *
 */

#include<stdio.h>

#define INPUT "divk.in"
#define OUTPUT "divk.out"

FILE *fin=fopen(INPUT, "r"),*fout=fopen(OUTPUT, "w");

long n,k,x,y,a[500001];
long long b[500001],total;

void citire();
void rezolva(long);

int main()
{
  citire();
  total=0;
  for(long i=x;i<=y;++i)
    rezolva(i);
  fprintf(fout, "%lld\n", total);
  fclose(fin);
  fclose(fout);
  return 0;
}

void citire()
{
  fscanf(fin, "%ld %ld %ld %ld", &n, &k, &x, &y);
  b[0]=0;
  for(long i=1;i<=n;++i)
  {
    fscanf(fin, "%ld", &a[i]);
    b[i]=b[i-1]+a[i];
  }
}

void rezolva(long x)
{
  for(long i=1;i<=n-x;++i)
    if((b[i+x-1]-b[i])%k==0)
      ++total;
}