#include <bits/stdc++.h>
using namespace std;
typedef long long int lli;
typedef long double ld;
typedef pair<ld, ld> pld;
typedef pair<lli, lli> pll;
#define mp(x, y) make_pair(x, y)
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
lli N, M;
cin >> N >> M;
lli a[N+1];
a[0] = 0;
for (lli i = 1; i <= N; i++) cin >> a[i];
for (lli i = 1; i <= N; i++) a[i] -= i*M;
reverse(a, a+N+1);
vector<lli> seq;
for (lli i = 0; i <= N; i++) {
if (seq.empty() || seq.back() <= a[i]) seq.push_back(a[i]);
else {
auto it = upper_bound(seq.begin(), seq.end(), a[i]);
*it = a[i];
}
}
for (lli i = seq.size()-1; i >= 0; i--) {
if (seq[i] == 0) {
cout << N-i;
return 0;
}
}
return 0;
}
