#include <fstream>

using namespace std;
int v[500001],s[500001];

int main()
{
    int N , A , B , K , i = 0 , contor = 0 , i1  , s1;
    ifstream f("divk.in");
    ofstream g("divk.out");
    f >> N >> K >> A >> B ;
    s[1] = 0 ;s[0] = 0 ;
    for(i = 1 ; i <= N ; ++ i)
    {
        f >> v[i];
        s[i] = s[i - 1] + v[i];
    }
    for(i = 1 ; i <= N ; ++i)
    {
        for(i1 = A + i - 1 ; i1 <= B + i ; ++i1)
        {
            if(i1 <= N)
              {
                s1 = s[i1] - s[i - 1];
                if(s1 % K == 0)
                    contor++;
              }
        }
    }
    g << contor ;

}