#include <bits/stdc++.h>
using namespace std;
#define _ ios_base::sync_with_stdio(0);cin.tie(0);
#define endl '\n'
#define int ll
typedef long long ll;
const int INF = 0x3f3f3f3f;
const ll LINF = 0x3f3f3f3f3f3f3f3fll;
const int MAX = 2e5+10, MOD = 1e9+7;
void solve(){
int n, m; cin >> n >> m; n++;
vector<int> v(n); int ans = 0;
for(int i = 1; i < n; i++) cin >> v[i];
for(int i = 0; i < n; i++){
if(i and v[i]-v[i-1] > m) ans++, v[i] = v[i-1]+m;
if(i < n-1 and v[i+1]-v[i] > m){
if(i == 0) ans++, v[i+1] = m;
else if(v[i-1]+m >= (v[i+1]-m)) v[i] = v[i+1]-m, ans++;
}
}
cout << ans << endl;
}
int32_t main(){ _
int ttt = 1; // cin >> ttt;
while(ttt--) solve();
exit(0);
}
