#include <bits/stdc++.h>
using namespace std;
const int MaxN = 200005;
int n, m;
long long a[MaxN], b[MaxN], k;
int dp[MaxN], aib[MaxN];
pair <int, int> c[MaxN];
void Update (int poz, int val) {
for (int i = poz; i <= n; i += (i & -i))
aib[i] = max(aib[i], val);
}
int Query (int poz) {
int val = 0;
for (int i = poz; i > 0; i -= (i & -i))
val = max(val, aib[i]);
return val;
}
int main()
{
cin >> n >> m;
for (int i = 1; i <= n; i++) {
cin >> a[i];
if (m * i >= a[i]) {
b[++k] = 1LL * m * i - a[i];
c[k] = {b[k], k};
}
}
sort (c + 1, c + k + 1);
int val = 1;
b[c[1].second] = 1;
for (int i = 2; i <= k; i++) {
if (c[i].first != c[i - 1].first)
val++;
b[c[i].second] = val;
}
int ans = 0;
if (k) {
ans = 1;
for (int i = 1; i <= k; i++) {
dp[i] = max(1, 1 + Query(b[i]));
Update(b[i], dp[i]);
ans = max(ans, dp[i]);
}
}
cout << n - ans << "\n";
return 0;
}
