#include<stdio.h>
int v[500002];
long long s1[500002];

int main()
{
    freopen("divk.in","r",stdin);
    freopen("divk.out","w",stdout);
    int n,k,a,b,i,j,sol=0;
    scanf("%d%d%d%d",&n,&k,&a,&b);
    for(i=1;i<=n;i++)
    {
        scanf("%d",&v[i]);
        //v[i]=v[i]%k;
    }
    for(i=1;i<=n;i++)
        s1[i]=s1[i-1]+v[i];
    //
    int max=n-a+1;
    for(i=1;i<=max;i++)
    {
        for(j=a-1;j<b&&i+j<=n;j++)
            if((s1[i+j]-s1[i-1])%k==0)
                sol++;
    }
    printf("%d\n",sol);
    return 0;
}