#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int N, K;
ll L, U, A[201010];
ll f(ll k){
    if(k < 0)return 1e18;
    ll cnt = 0;
    for(int i = 0;i < N;i++){
        if(A[i] < k){
            cnt += (k - A[i] + K - 1) / K;
        }
        if(A[i] > k + U - L){
            cnt += (A[i] - (k + U - L) + K - 1) / K;
        }
    }
    return cnt;
}
int main(void){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    cin >> N >> K >> L >> U;
    for(int i = 0;i < N;i++)cin >> A[i];
    ll l = 0, r = 1e12;
    while(r - l > 2){
        ll m1 = (l + l + r) / 3;
        ll m2 = (l + r + r) / 3;
        if(f(m1) >= f(m2))l = m1;
        else r = m2;
    }
    cout << min({f(l), f(l + 1), f(l + 2)}) << endl;
    return 0;
}