#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define maxn 200005
#define FOR(i , a , b) for(int i = a ; i <= b; i++)
#define FAST ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
ll a[maxn] , b[maxn];
int main(){
FAST;
int n;
ll M;
cin >> n >> M;
FOR(i , 1 , n) cin >> a[i];
FOR(i , 1 , n) if(M * i >= a[i]) a[i] = M * i - a[i];
FOR(i , 1 , n) b[i] = 1e18;
int ans = 0;
FOR(i , 1 , n){
int k = upper_bound(b + 1, b + n + 1, a[i]) - b;
b[k] = a[i];
ans = max(ans , k);
}
cout << n - ans;
}
