#include <bits/stdc++.h>
using namespace std;
#define int long long
void update(vector<int>&tree, int v, int tl, int tr, int k, int x) {
if (tl == tr) tree[v] = max(tree[v], x);
else {
int tm = (tl + tr)/2;
if (k <= tm) update(tree, v*2, tl, tm, k, x);
else update(tree, v*2 + 1, tm + 1, tr, k, x);
tree[v] = max(tree[v*2], tree[v*2 + 1]);
}
}
int query(vector<int>&tree, int v, int tl, int tr, int l, int r) {
if (l > r) return -1e18;
else if(tl == l && tr == r) return tree[v];
else {
int tm = (tl + tr)/2;
return max(query(tree, v*2, tl, tm, l, min(tm, r)), query(tree, v*2 + 1, tm + 1, tr, max(tm + 1, l), r));
}
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, m;
cin >> n >> m;
vector<int> diff(n + 5);
map<int, int> mp = {{0, 1}};
for (int i = 1; i <= n; i++) {
int h;
cin >> h;
diff[i] = h - m*i;
mp[diff[i]]++;
}
int cnt = 0;
for (auto&v : mp) v.second = cnt++;
vector<int> dp(n + 5, -1e18), tree(4 * n + 5, -1e18);
diff[0] = mp[diff[0]];
dp[0] = 0;
update(tree, 1, 0, n, diff[0], dp[0]);
for (int i = 1; i <= n; i++) {
diff[i] = mp[diff[i]];
dp[i] = 1 + query(tree, 1, 0, n, diff[i], n);
update(tree, 1, 0, n, diff[i], dp[i]);
}
cout << n - *max_element(dp.begin(), dp.begin() + n + 1) << '\n';
return 0;
}
