#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
#define ll long long
// No I totally didn't make an alt because I forgot my email and password who would do such a thing :P
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
ll n, m;
cin >> n >> m;
vector<ll> v;
for (int i = 0; i < n; ++i) {
ll a;
cin >> a;
if (m * (i + 1) - a > 0) {
a = m * (i + 1) - a;
auto it = upper_bound(v.begin(), v.end(), a);
if (it == v.end()) {
v.push_back(a);
}
else {
v[it - v.begin()] = a;
}
}
}
cout << n - (ll)v.size() << '\n';
return 0;
}
