#include<cstdio>
using namespace std;
int n,k,a,b,nr,v[500005];
int main()
{
    int i,j;
    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",&v[i]), v[i]%=k;
    for (i=0;i<=n-a;++i)
        for (j=i+a;j<=i+b && j<=n;++j)
            if (v[i]==v[j]) ++nr;
    printf("%d\n",nr);
    return 0;
}