#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }
#define COLOR(s) ("\x1b[" s "m")


// floor(a / b)
Int divFloor(Int a, Int b) {
  return a / b - (((a ^ b) < 0 && a % b != 0) ? 1 : 0);
}

// ceil(a / b)
Int divCeil(Int a, Int b) {
  return a / b + (((a ^ b) > 0 && a % b != 0) ? 1 : 0);
}


constexpr Int INF = 100100100100100100LL;

int N;
Int K, L, U;
vector<Int> A;
Int W;

// [b, b + W]
Int calc(Int b) {
  const Int c = b + W;
  Int ret = 0;
  for (int i = 0; i < N; ++i) {
    if (A[i] < b) {
      ret += ((b - A[i]) + K - 1) / K;
    }
    if (c < A[i]) {
      ret += ((A[i] - c) + K - 1) / K;
    }
  }
  return ret;
}

int main() {
  for (; ~scanf("%d%lld%lld%lld", &N, &K, &L, &U); ) {
    A.resize(N);
    for (int i = 0; i < N; ++i) {
      scanf("%lld", &A[i]);
    }
    W = U - L;
    sort(A.begin(), A.end());
    
    Int lo = divFloor(A[0] - W, K) - 1;
    Int hi = divCeil(A[N - 1] + W, K) + 1;
    for (; lo + 1 < hi; ) {
      const Int mid = (lo + hi) / 2;
      ((calc(K * mid) > calc(K * (mid + 1))) ? lo : hi) = mid;
    }
    
    const Int bL = K * (hi - 1);
    const Int bR = K * (hi + 1);
cerr<<"W = "<<W<<", [bL, bR] = ["<<bL<<", "<<bR<<"]"<<endl;
    vector<Int> fs(bR - bL + 1, 0);
    fs[0] += calc(bL);
    for (int i = 0; i < N; ++i) {
      for (Int b = A[i] + max(divCeil(bL - A[i], K), 0LL) * K + 1; b <= bR; b += K) {
        ++fs[b - bL];
      }
      for (Int c = A[i] - max(divCeil(A[i] - (bR + W), K), 0LL) * K; c > bL + W; c -= K) {
        --fs[c - W - bL];
      }
    }
    for (Int b = bL + 1; b <= bR; ++b) {
      fs[b - bL] += fs[b - 1 - bL];
    }
    
    const Int ans = *min_element(fs.begin(), fs.end());
    printf("%lld\n", ans);
#ifdef LOCAL
cerr<<"fs = "<<fs<<endl;
// for(Int b=bL;b<=bR;++b)cerr<<calc(b)<<" ";cerr<<endl;
for(Int b=bL;b<=bR;++b)assert(calc(b)==fs[b-bL]);
#endif
  }
  return 0;
}