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