//#pragma GCC optimize("O3")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("avx,avx2")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,avx,avx2")
//#pragma GCC optimize("trapv")
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pb push_back
#define all(x) x.begin(), x.end()
#define mpr make_pair
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
const int nmax = 200011, mod = 1000000007, inf = 2000010000, key = 200003, lg = 20, block = 300;
const ll infll = 4000000000000000000;
const ld eps = 1e-9;
void solve()
{
int n, m;
cin >> n >> m;
vector<int> dp;
dp.pb(0);
for(int i = 1; i <= n; i++) {
int a;
cin >> a;
a -= i * m;
if(a > 0)
continue;
if(a <= dp.back())
dp.pb(a);
else
dp[upper_bound(all(dp), a, greater<int>()) - dp.begin()] = a;
}
cout << n - dp.size() + 1 << "\n";
return ;
}
int main()
{
//freopen("palpath.in","r",stdin);
//freopen("palpath.out","w",stdout);
ios_base::sync_with_stdio(0);cin.tie(0);
srand(8713);
//init();
int t = 1;
//cin >> t;
//int t_ = t;
//t = rdi();
while(t--) {
//cout << "Case #" << t_ - t << ": ";
solve();
}
//flush();
return 0;
}
/*
*/
