#include <iostream>
#include <queue>
#include <algorithm>
using namespace std;
const long long MAXN = 2e5+5;
long long arr[MAXN];
long long d[MAXN];
int main(){
long long n,k;
cin>>n>>k;
const long long INF = 1e18;
vector<long long> d(n+2, -INF);
d[n+1] = 0;
for(long long i=1;i<=n;i++){
cin>>arr[i];
arr[i]-=(k*i);
}
for(long long i=1;i<=n;i++){
long long j = lower_bound(d.begin(), d.end(), arr[i]) - d.begin();
if(j<=(n+1) && d[j-1]<=arr[i] && d[j]>=arr[i]){
d[j-1] = arr[i];
}
// cout<<arr[i]<<" "<<j<<endl;
}
long long ans = 0;
for(long long i=1;i<=n;i++){
if(d[i]!=-1e18){
ans = max(ans,n-i+1);
}
}
cout<<n-ans<<endl;
return 0;
}
