#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pr pair<int, int>
#define prr pair<pr, int>
#define f first
#define s second
#define pr pair<int, int>
#define pb push_back
const int ndim=2e5+1;
vector<int> par(ndim);
vector<int> psize(ndim);
int main(){
int n, m; cin>>n>>m;
vector<int> a(n), d;
for (int i=0; i<n; i++) cin>>a[i];
for (int i=0; i<n; i++) {
if(m*(i+1)-a[i]>=0) d.pb(m*(i+1)-a[i]);
}
//for (auto e: d) cout<<e<<" ";
//cout<<endl;
vector<int> st;
for (int i=0; i<(int)d.size(); i++){
if(i==0) {st.pb(d[i]); continue; }
auto it=upper_bound(st.begin(), st.end(), d[i]);
int pos=upper_bound(st.begin(), st.end(), d[i])-st.begin();
if(it==st.end()) st.pb(d[i]);
else{
st[pos]=d[i];
}
//for (auto e: st) cout<<e<<" ";
//cout<<endl;
}
cout<<n-st.size()<<endl;
}
