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