#include<fstream>
using namespace std;
ifstream f("divk.in");
ofstream g("divk.out");
long long n,m,t,a,p,q,b,s,i,j,k,v[500001];
int main()
{f>>n>>k>>a>>b;
for(i=1;i<=n;++i)
	f>>v[i];
m=n-a+1;
t=0;
for(i=1;i<=m;++i)
{s=0;
p=i+a-1; q=i+b-1;
for(j=i;j<=p;++j)
	s=(s+v[j])%k;
if(s==0)
	++t;
while(p<q)
{++p;
s=(s+v[p])%k;
if(s==0)
	++t;
}
}
g<<t;
return 0;
}