#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;
int main() {
int n, m;
cin >> n >> m;
vector<int> arr(n);
for (int i = 0; i < n; i++) {
cin >> arr[i];
}
vector<int> seq;
for (int i = 1; i <= n; i++) {
if (i * m >= arr[i - 1]) {
seq.push_back(i * m - arr[i - 1]);
}
}
vector<int> minEndings;
for (int i : seq) {
int pos = upper_bound(minEndings.begin(), minEndings.end(), i) - minEndings.begin();
if (pos == minEndings.size()) {
minEndings.push_back(i);
}
else {
minEndings[pos] = i;
}
}
cout << n - minEndings.size() << endl;
return 0;
}
