#include <iostream>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <algorithm>
#include <cstring>
#include <cstdio>
#include <fstream>
#include <sstream>
using namespace std;
typedef long long ll;

ll Xs[110];
map<ll, vector< pair<ll, ll> > > intervals;

int main(){
    ll N, D, T;
    cin >> N >> D >> T;
    
    for(int i=0;i<N;i++)cin >> Xs[i];
    sort(Xs, Xs + N);
    
    for(int i=0;i<N;i++){
        ll X = Xs[i];
        
        ll mod = (X % D + D) % D;
        intervals[mod].push_back(make_pair(X - D * T, X + D * T));
    }
    
    ll res = 0;
    
    map<ll, vector< pair<ll, ll> > >::iterator itr;
    for(itr = intervals.begin(); itr != intervals.end(); itr++){
        vector< pair<ll, ll> > vs = itr->second;
        
        ll sum = 0;
        ll p = -1ll << 60;
        
        for(int i=0;i<vs.size();i++){
            sum += max(0ll, vs[i].second - max(p, vs[i].first));
            p = max(p, vs[i].second);
        }
        
        res += sum / D + 1;
    }
    
    cout << res << endl;
    
    
    return 0;
}