/*#pragma GCC optimize("Ofast,no-stack-protector,unroint-loops,fast-math,O3")
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization("unroint-loops")
#pragma ("reroint") */
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define ins insert
#define F first
#define S second
const int mod = 1e9 + 7,N = 2e5 + 100,mx = 1e9 + 7;
int a[N];
signed main(){
//freopen("justcoding.in","r",stdin);
//freopen("justcoding.out","w",stdout);
std::ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int n,m;
cin >> n >> m;
vector < int > b;
for(int i = 1;i<=n;i++){
cin >> a[i];
a[i] -= i * m;
if(a[i] <= 0) b.pb(a[i] * -1);
}
int mx = 0;
vector<int>v;
v.pb(0);
bool ok = 0;
for(int i = 0;i<b.size();i++){
auto it = upper_bound(v.begin(),v.end(),b[i]);
int ans = it - v.begin();
if(v[v.size()-1]<=b[i]) v.pb(b[i]);
else {
//if(ans==0) ok = 1;
//cout << i << ' ' << ans << '\n';
v[ans] = b[i];
}
}
cout << n - (v.size() - (ok==0));
}
