#include <cstdio>
using namespace std;
int i,j,n,k,a,x,nr,b,s[500005];
int main()
{
    freopen("divk.in","r",stdin);
    freopen("divk.out","w",stdout);
    scanf("%d%d%d%d",&n,&k,&a,&b);
    for(i=1;i<=n;i++){
        scanf("%d",&x);
        s[i]=s[i-1]+x;
    }
    for(i=0;i<=n-b;i++){
        for(j=a+i;j<=b+i;j++){
            if((s[j]-s[i])%k==0){
                nr++;
            }
        }
    }
    for(;i<=n-a;i++){
        for(j=a+i;j<=n;j++)
             if((s[j]-s[i])%k==0) nr++;
    }
    printf("%d",nr);
}