#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=n-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define vtpl(x,y,z) vector<tuple<x,y,z>>
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e18;
const ll dy[9]={0,0,1,-1,1,1,-1,-1,0};
const ll dx[9]={1,-1,0,0,1,-1,1,-1,0};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
int main(){
    ll n,d,t;cin >> n >> d >> t;
    vl v(n);rep(i,n)cin >> v[i];
    map<ll,queue<ll>> mp;
    rep(i,n){
        mp[(v[i]+d*inf)%d].push(v[i]);
    }
    ll ans=0;
    for(auto p:mp){
        auto que=p.se;
        vl l,r;
        ll z=que.front();que.pop();
        l.pb(z-d*t);r.pb(z+d*t);
        while(!que.empty()){
            ll z=que.front();que.pop();
            ll left=z-d*t,right=z+d*t;
            if(*r.rbegin()+d>=left){
                r[r.size()-1]=right;
            }
            else{
                l.pb(left);r.pb(right);
            }
        }
        rep(i,l.size())ans+=(r[i]-l[i])/d+1;
    }
    cout << ans <<endl;
}