#include <bits/stdc++.h> using namespace std; #define int long long #define name "ojuz" #define MAXN 200005 #define pb push_back #define pf push_front #define ll long long #define ii pair<int, int> #define fs first #define sc second #define ill pair<int, ll> #define lli pair<ll, int> #define llll pair<ll, ll> #define all(v) v.begin(),v.end() #define uni(v) v.erase(unique(all(v)),v.end()) #define bit(n,i) (((n)>>(i))&1) #define FOR(i,a,b) for (int i=(a),_b=(b); i<=_b; i++) #define FORD(i,a,b) for (int i=(a),_b=(b); i>=_b; i--) #define MASK(i) (1LL<<(i)) const int INF=1e9; const int MOD=1e9+7; void add(int &u, int v){ u+=v; if (u>=MOD) u-=MOD; } void sub(int &u, int v){ u-=v; if (u<0) u+=MOD; } void minimize(int &u, int v){ u=min(u,v); } void maximize(int &u, int v){ u=max(u,v); } long long Rand(long long l, long long r){ ll tmp=0; FOR(i,1,4) tmp=((tmp<<15)^(((1<<15)-1)&rand())); return l+tmp%(r-l+1); } int n,m; int a[MAXN]; int bit[MAXN],dp[MAXN]; void update(int x, int val){ for (; x>0; x-=x&-x) maximize(bit[x],val); } int get(int x){ int res=-INF; for (; x<MAXN; x+=x&-x) maximize(res,bit[x]); return res; } int32_t main() { ios::sync_with_stdio(0), cin.tie(0), cout.tie(0); cin>>n>>m; FOR(i,1,n) cin>>a[i]; FOR(i,1,n) a[i]-=i*m; vector<int> store; FOR(i,0,n) store.pb(a[i]); sort(all(store)); uni(store); FOR(i,0,n) a[i]=lower_bound(all(store),a[i])-store.begin()+1; memset(bit,-0x3f,sizeof(bit)); update(a[0],0); /* FOR(i,0,n) cout<<a[i]<<" "; cout<<"\n"; */ FOR(i,1,n){ if (a[i]>a[0]) continue; dp[i]=get(a[i]); if (dp[i]>=0) dp[i]++; update(a[i],dp[i]); } cout<<n-(*max_element(dp+1,dp+n+1)); return 0; }