#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<complex>
#include<bitset>
#include<stack>
#include<unordered_map>
using namespace std;
typedef long long ll;
typedef unsigned int ui;
const ll mod = (ll)(1e+9) + 7;
const ll INF = (ll)1000000007 * 1000000007;
typedef pair<int, int> P;
#define stop char nyaa;cin>>nyaa;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
typedef long double ld;
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<ll, ll> LP;
typedef pair<ld, ld> LDP;
ll x[100];
bool used[100];
int main() {
	int n; cin >> n;
	ll d, t; cin >> d >> t;
	rep(i, n) {
		cin >> x[i];
	}
	sort(x, x + n);
	ll out = 0;
	rep(i, n) {
		if (used[i])continue;
		ll ri = x[i] + d * t;
		ll s = x[i] - d * t;
		Rep(j, i + 1, n) {
			if (used[j])continue;
			if ((x[j] - x[i]) % d == 0){
				used[j] = true;
				ll le = x[j] - d * t;
				if (le <= ri) {
					ri = x[j] + d * t;
				}
				else {
					out += (ri - s) / d + 1;
					s = le; ri = x[j] + d * t;
				}
		    }
		}
		out += (ri - s) / d + 1;
	}
	cout << out << endl;
	//stop
	return 0;
}