#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define endl '\n'
#define mask(i) (1LL << (i))
#define ull unsigned long long
#define ld long double
using namespace std;
const int mxN = 3e5 + 227;
const ll inf = 1e9 + 277;
const int mod = 1e9 + 7;
const ll infll = 1e18 + 7;
const int base = 307;
const int LOG = 20;
template <typename T1, typename T2> bool minimize(T1 &a, T2 b) {
if (a > b) {a = b; return true;} return false;
}
template <typename T1, typename T2> bool maximize(T1 &a, T2 b) {
if (a < b) {a = b; return true;} return false;
}
int a[mxN];
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
//freopen("task.inp" , "r" , stdin);
//freopen("task.out" , "w" , stdout);
int n , limit;
cin >> n >> limit;
for(int i = 1 ; i <= n ; i++) cin >> a[i];
vector<int> lis;
for(int i = 1 ; i <= n ; i++) {
a[i] -= (limit * i);
a[i] = -a[i];
if(a[i] < 0) continue;
//cout << a[i] << ' ';
int pos = upper_bound(lis.begin() , lis.end() , a[i]) - lis.begin();
if(pos == (int) lis.size()) lis.push_back(a[i]);
else lis[pos] = a[i];
}
cout << n - (int) lis.size();
return 0;
}
