using namespace std;
#include<iostream>
#include<fstream>
long long sol=0;
int A,B,N,K,s[500005],a[500005];
ofstream fout("divk.out");
void solve()
{int i,j;
    for(i=1;i<=N;i++)
    {
        for(j=i+A-1;j<=i+B-1&&j<=N;j++)
         if(s[j]-s[i-1]==0)
          sol++;
    }
    fout<<sol;
}
void cit()
{s[0]=0;
int i;
    ifstream fin("divk.in");
    fin>>N>>K>>A>>B;
    for(i=1;i<=N;i++)
    { fin>>a[i];
    a[i]%=K;
    s[i]=s[i-1]+a[i];
    s[i]%=K;
    }
    fin.close();


}
int main()
{

    cit();
    solve();
    fout.close();
    return 0;
}