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

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

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;
    ll base = (X - mod) / D;
    eventsMap[mod].push_back(make_pair(base - T, base + T + 1));
  }
    
  ll res = 0;
  for(auto ps : eventsMap) {
    auto events = ps.second;
    
    ll p = -1ll << 60;
    for(auto ev : events) {
      res += max(0ll, ev.second - max(p, ev.first));
      p = max(p, ev.second);
    }
  }
    
  cout << res << endl;
  return 0;
}