#define _USE_MATH_DEFINES
 
#include <iostream>
#include <iomanip>
 
#include <algorithm>
#include <cmath>
 
#include <string>
//#include <array>
#include <list>
#include <queue>
#include <vector>
#include <complex>
#include <set>
#include <map>
 
/////////
#define REP(i, x, n) for(int i = x; i < n; i++)
#define rep(i,n) REP(i,0,n)
#define P(p) cout<<(p)<<endl;
 
#define PII pair<int,int>
/////////
typedef long long LL;
typedef long double LD;
/////////
using namespace::std;
/////////

int main(void){
    std::cin.tie(0); 
    std::ios::sync_with_stdio(false);
    std::cout << std::fixed;//
    //cout << setprecision(10);//
	
	int N,D,T;
	cin>>N>>D>>T;
	int X[100];
	rep(i,N){
		cin>>X[i];
	}
	//////
	int t[100];
	int tCount = 0;
	int tNo,tNoi,Len;
	vector<PII> v[100];
	rep(i,N){
		if( X[i] >= 0 ){
			tNoi = X[i]%D;
			Len = X[i]/D;
		}else{
			tNoi = D+X[i]%D;
			Len = (D+X[i]+X[i]%D-1)/D -1;
		}
		for(tNo=0;tNo<tCount;++tNo){
			if( t[tNo] == tNoi){
				break;
			}
		}
		if(tNo >= tCount){
			t[tCount] = tNoi;
			++tCount;
		}
		v[tNo].push_back( PII(Len,Len) );
	}
	rep(i,tCount){
		sort( v[i].begin(),v[i].end() );
	}
	rep(i,tCount){
		vector<PII>::iterator itr = v[i].begin();
		while((itr+1) != v[i].end() ){
			if( ( (itr+1)->first - itr->second )/2 <= T ){
				itr->second = (itr+1)->second;
				v[i].erase(itr+1);
			}else{
				++itr;
			}
		}
	}
	LL ans = 0;
	rep(i,tCount){
		vector<PII>::iterator itr = v[i].begin();
		while( itr != v[i].end() ){
			if(itr->first == itr->second){
				ans += 2*T+1;
			}else{
				ans += itr->second - itr->first + 1 + 2*T;
			}
			++itr;
		}
	}
	P(ans);
    return 0;
}