#include <bits/stdc++.h>
using namespace std;
#define all(v) v.begin(),v.end()
#define eb emplace_back
#define ll long long
#define fi first
#define se second
int t,n,i;
ll m;
const int maxn = 2e5 + 10;
ll a[maxn],b[maxn];
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin>>n>>m;
vector<ll> tmp;
for(i = 1;i<=n;i++)
{
cin>>a[i];
b[i] = m * i - a[i];
if(b[i] < 0)continue;
if(tmp.empty() || tmp.back() <= b[i])
{
tmp.eb(b[i]);
}
else *upper_bound(all(tmp),b[i]) = b[i];
}
cout<<n - tmp.size();
return 0;
}
