(n, d) = map(int, input().split(' '))
x = list(map(int, input().split(' ')))
hotels = []
x.append(0)
for i in range(n):
if i == 0:
if x[i] + d <= x[i + 1] - d:
hotels.append(x[i] + d)
else:
if x[i - 1] + d <= x[i] - d:
hotels.append(x[i] - d)
if x[i] + d <= x[i + 1] - d:
hotels.append(x[i] + d)
hotels.append(x[0] - d)
hotels.append(x[-2] + d)
print(len(set(hotels)))
/* Hello Ji */
#include<bits/stdc++.h>
#define ll long long
const int MOD = 1e9 + 7;
#define pb push_back
#define endl "\n"
#define quick ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
using namespace std;
// bool comp(pair<ll,ll> &p1,pair<ll,ll> &p2)
// {
// return p1.second<p2.second;
// }
void solve()
{
ll n,d;
cin>>n>>d;
ll a[n];
for(int i=0;i<n;i++){
cin>>a[i];
}
ll count = 0;
for(int i=0;i<n-1;i++){
if(a[i+1]-a[i]==2*d){
count++;
}
else if(a[i+1]-a[i]>2*d){
count = count + 2;
}
}
cout << count + 2 << endl;
}
int32_t main()
{
quick;
int t = 1;
// cin>>t;
while(t--)
{
solve();
}
cerr << "time taken : " << (float)clock() / CLOCKS_PER_SEC << " secs" << endl;
return 0;
}
/*
*/
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518. Coin Change 2 | 516. Longest Palindromic Subsequence |
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