#include<bits/stdc++.h>
#define IOS ios_base::sync_with_stdio(false);cin.tie();cout.tie();
#define all(x) x.begin(), x.end()
#define int long long
#define pq priority_queue
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define pb push_back
#define pp pop_back
#define F first
#define S second
using namespace std;
void solve () {
int n, m; cin >> n >> m;
vector<int> a(n);
for (auto &i: a) cin >> i;
vector<int> v;
for (int i = 1; i <= n; i++) if (i * m >= a[i-1]) v.pb(i * m - a[i-1]);
vector<int> dp;
for (int i: v) {
int p = ub(all(dp), i) - dp.begin();
if (p == dp.size()) dp.pb(i);
else dp[p] = i;
}
cout << n - dp.size();
}
signed main() {IOS solve(); return 0;}
