#include<bits/stdc++.h>
#include<random>
using namespace std;
using db=double;
using ll=long long;
using sll=__int128;//super long long
using lb=long double;//lb is slow
//numbers for hashing: b(19260817),mod(998244353)
// freopen("lasers.in", "r", stdin);
// freopen("lasers.out", "w", stdout);
class BinaryIndexedTree{
private:
vector<ll>bit;
public:
BinaryIndexedTree(ll n){
bit.resize(n+1);
}
void update(ll index, ll delta){
while(bit.size()>index){
bit[index]=min(bit[index],delta); index+=index&-index;
}
}
ll query(ll index){
ll mx=1e18;
while(index>0){
mx=min(mx,bit[index]); index-=index&-index;
}
if(mx==1e18)mx=0;
return mx;
}
};
int main(){
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
ll n,m; cin>>n>>m; vector<ll>a(n+1); map<ll,vector<ll>>mp; vector<ll>c(n+1);
for(ll i=1; i<=n; i++){
cin>>a[i]; c[i]=a[i]; a[i]-=i*m; mp[a[i]].push_back(i);
}
mp[a[0]].push_back(0); vector<ll>b(n+1); ll count=n+10;
for(auto x:mp){
count--;
for(auto y:x.second){
b[y]=count;
}
}
BinaryIndexedTree BIT(n+13); vector<ll>dp(n+1); ll start=1;
while(c[start]-m>c[start-1] && start<=n){
c[start]=c[start-1]; start++;
}
for(ll i=start; i<=n; i++){
dp[i]=i-1+BIT.query(b[i]);
BIT.update(b[i],dp[i]-i);
}
cout<<dp[n]+start-1<<'\n';
}
