#include <stdio.h>
#include <stdlib.h>

int v[500001];

int main()
{
    int n,k,a,b,q,s=0,i;
    FILE*fi,*fo;
    fi=fopen("divk.in","r");
    fo=fopen("divk.out","w");
    fscanf(fi,"%d%d%d%d",&n,&k,&a,&b);
    for(i=0;i<n;i++){
        fscanf(fi,"%d",&q);
        v[i+1]=v[i]+q%k;
    }
    for(q=a-1;q<b;q++)
        {
            for(i=1;i+q<=n;i++)
                if((v[i+q]-v[i-1])%k==0){
                    s++;
                }
        }
    fprintf(fo,"%d",s);
    fclose(fi);
    fclose(fo);
    return 0;
}