#include<stdio.h>
#define maxn 500001
long n,k,a,b,i,j;
long long s,v[maxn];
int t;
FILE *f,*g;
int main()
{f=fopen("divk.in","r");
g=fopen("divk.out","w");
fscanf(f,"%ld %ld %ld %ld",&n,&k,&a,&b);
for(i=1;i<=n-a+1;i++)
{fscanf(f,"%lld",&v[i]);v[i]=v[i]+v[i-1];}
for(i=1;i<=n;i++)
for(j=i+a-1;j<=i+b-1&&j<=n;j++)
if((v[j]-v[i-1])%k==0)
t++;
fprintf(g,"%d",t);
return 0;}