/* -*- coding: utf-8 -*-
 *
 * 33.cc: No.33 アメーバがたくさん - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 100;

/* typedef */

typedef long long ll;
typedef vector<int> vi;
typedef queue<int> qi;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<pll> vpll;
typedef map<int,vpll> mivpl;

/* global variables */

ll xs[MAX_N];
mivpl rgs;

/* subroutines */

/* main */

int main() {
  int n, d, t;
  cin >> n >> d >> t;

  for (int i = 0; i < n; i++) {
    ll xi;
    cin >> xi;

    ll x0 = xi - (ll)t * d;
    ll x1 = xi + (ll)t * d;
    int mod = (xi % d + d) % d;
    vpll &rgv = rgs[mod];
    //printf("xi=%lld, mod=%d\n", xi, mod);

    rgv.push_back(pll(x0, x1 + d));
  }

  ll cnt = 0;
  for (mivpl::iterator mit = rgs.begin(); mit != rgs.end(); mit++) {
    vpll &rgv = mit->second;
    sort(rgv.begin(), rgv.end());

    pll r = rgv[0];
    for (int i = 1; i < rgv.size(); i++) {
      if (r.second < rgv[i].first) {
	cnt += (r.second - r.first) / d;
	r = rgv[i];
      }
      else
	r.second = rgv[i].second;
    }
    cnt += (r.second - r.first) / d;
  }

  printf("%lld\n", cnt);
  return 0;
}