#define _CRT_SECURE_NO_WARNINGS
#include<sstream>
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<climits>
#include<cmath>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<numeric>
#include<functional>
#include<algorithm>
#include<bitset>
#include<tuple>
#include<unordered_set>
#include<random>
using namespace std;
#define INF (1<<29)
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(v) v.begin(),v.end()
#define uniq(v) v.erase(unique(all(v)),v.end())
#define indexOf(v,x) (find(all(v),x)-v.begin())


int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	map<int,vector<int>> mp;
	int n,d,t;
	cin>>n>>d>>t;
	rep(i,n){
		int x;
		cin>>x;
		x+=1000000000;
		mp[x%d].push_back(x/d);
	}
	long long ans=n;
	for(auto p : mp){
		sort(all(p.second));
		uniq(p.second);
		int prev=p.second.front()-1;
		for(auto x : p.second){
			ans+=min(2*t,x-prev-1);
			prev=x;
		}
		ans+=2*t;
	}
	cout<<ans<<endl;
	return 0;
}