#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <array>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <fstream>
#include <complex>
#include <cstring>
#include <unordered_map>
#include <unordered_set>
using namespace std;

using ll = long long;
constexpr int INF = 1001001001;
constexpr int mod = 1000000007;
// constexpr int mod = 998244353;

template<class T>
inline bool chmax(T& x, T y){
    if(x < y){
        x = y;
        return true;
    }
    return false;
}
template<class T>
inline bool chmin(T& x, T y){
    if(x > y){
        x = y;
        return true;
    }
    return false;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int N;
    ll D, T, X;
    cin >> N >> D >> T;
    map<int, vector<pair<ll, ll>>> section;
    for(int i = 0; i < N; ++i){
        cin >> X;
        int m = (X % D + D) % D;
        section[m].emplace_back(X - D * T, X + D * T);
    }
    ll ans = 0;
    for(auto& [m, v] : section){
        sort(begin(v), end(v));
        v.emplace_back(7e+18, 7e+18);
        ll low = v[0].first, high = v[0].second;
        for(auto& [l, r] : v){
            if(l > high){
                ans += (high - low) / D + 1;
                low = l;
            }
            chmax(high, r);
        }
    }
    cout << ans << endl;
    
    return 0;
}