#include<stdio.h>
const int C=9001,N=500001;
int sum[N],f[N];
int main()
{
    freopen("divk.in","r",stdin);
    freopen("divk.out","w",stdout);
    int n,i,x,A,B,K;
    scanf("%d%d%d%d",&n,&K,&A,&B);
    long long rez=0;

    for(i=1;i<=n;i++)
    {
        scanf("%d",&x);
        sum[i]=(sum[i-1]+x)%K;

        f[sum[i]]++;
        if(f[sum[i]]>=A)
            if(f[sum[i]]<=B)
                rez+=(f[sum[i]]-1);
            else rez+=B;
    }

    printf("%d",rez);
}