#include <bits/stdc++.h>
#define io ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0)
#define int long long
using namespace std;
int f(const vector<int>& s) {
vector<int> m;
for (int x : s) {
int p = upper_bound(m.begin(), m.end(), x) - m.begin();
if (p == (int)m.size()) m.push_back(x);
else m[p] = x;
}
return m.size();
}
signed main() {
io;
int n, m;
cin >> n >> m;
vector<int> a(n);
for (int i = 1; i <= n; ++i) cin >> a[i - 1];
vector<int> b;
for (int i = 1; i <= n; ++i) {
int v = i * m - a[i - 1];
if (v >= 0) b.push_back(v);
}
cout << n - f(b);
}
