#include <iostream>
#include <fstream>


using namespace std;

ifstream fin("divk.in");
ofstream fout("divk.out");

int n, k, a, b;
int sum;
int fr[100000];
long long sol;

int main()
{
    fin>>n>>k>>a>>b;
    int x;
    for(int i=1; i<=n; i++){
        fin>>x;
        sum = (sum + x) % k;
        if(i >= a && i <= b) fr[sum]++;
    }

    sol = (fr[0]*(fr[0]+1))/2;
    for(int i=1; i<k; i++)
        sol = sol + (fr[i]*(fr[i]+1))/2;

    fout<<sol;

    return 0;
}