#include<fstream>
#include<vector>

using namespace std;

ifstream cin("divk.in");
ofstream cout("divk.out");
const int N = 10000005;
vector<int> pref;
int n, k;

long long find_ans(int b)
{
  vector<int> cnt(k, 0);
  long long ans = 0;

  for(int i = 0; i < b; ++i)
    ans += cnt[pref[i]]++;

  for(int i = b; i <= n; i ++)
    cnt[pref[i-b]]-- , ans += cnt[pref[i]]++;
  return ans;
}

int main()
{
  
  int s, e;
  cin >> n >> k >> s >> e;
  pref.resize(n+1);
  for(int i = 1; i <= n; i ++)
    cin >> pref[i];

  pref[0] = 0;
  for(int i = 1; i <=n ; i++)
    pref[i] = (pref[i] + pref[i-1]) % k;
  
  cout << find_ans(e+1) - find_ans(s) << "\n";

  return 0;
}