#include <iostream>
#include <vector>
using namespace std;
const int MAXN = 2e6 + 123;
vector<int> edg[MAXN];
int rt[MAXN];
int init(int n) {
int t;
cin >> t;
vector<int> a(n);
for (int i = 0; i < n; ++i)
cin >> a[i];
vector<pair<int, int>> stck;
vector<int> vl(n);
int ans = 0;
for (int i = 0; i < n; ++i) {
stck.push_back({a[i], i});
while (stck.size() && t - stck.back().first < i - stck.back().second)
stck.pop_back();
if (stck.size()) {
vl[i] = stck.back().second;
} else {
++ans;
vl[i] = n + 1;
}
}
//for (int i = 0; i < n; ++i)
//cout << vl[i] << ' ';
//cout << endl;
vector<int> way;
for (int i = n - 1; i >= 0; --i) {
while (way.size() && vl[way.back()] > i) {
way.pop_back();
}
if (vl[i] >= i) {
rt[i] = -1;
continue;
}
if (vl[i] < i && way.size()) {
rt[i] = way.back();
edg[way.back()].push_back(i);
} else {
rt[i] = 0;
edg[0].push_back(i);
}
way.push_back(i);
}
//for (int i = 0; i < n; ++i) {
//cout << rt[i] << ' ';
//}
//cout << endl;
return ans;
}
vector<int>* unite(vector<int>* a, vector<int>* b, int d) {
int n = a->size();
if ((*a)[0]) {
for (int i = 1; i < n; ++i)
(*a)[i] += (*a)[0];
(*a)[0] = 0;
}
int m = b->size();
if ((*b)[0]) {
for (int i = 1; i < m; ++i)
(*b)[i] += (*b)[0];
(*b)[0] = 0;
}
if (n < m)
swap(a, b);
int sz = min(d + 1, n + m - 1);
a->resize(sz);
for (int i = sz - 1; i > 0; --i) {
for (int j = 0; j < m && j <= i; ++j) {
(*a)[i] = max((*a)[i], (*a)[i - j] + (*b)[j]);
}
}
delete b;
return a;
}
vector<int>* dfs(int v, int d) {
if (edg[v].empty()) {
vector<int>* ans = new vector<int>(2);
(*ans)[1] = 1;
return ans;
}
vector<int>* ans = nullptr;
for (auto u : edg[v]) {
if (!ans) {
ans = dfs(u, d);
} else {
ans = unite(ans, dfs(u, d), d);
}
}
++(*ans)[0];
//cout << v << ": ";
//for (auto x : ans)
//cout << x << ' ';
//cout << endl;
return ans;
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
int n, d;
cin >> n >> d;
int neut = init(n);
vector<int>* vvv = dfs(0, d);
int ans = vvv->front() + vvv->back();
//cout << "(" << ans << ' ' << neut << ") " << endl;
cout << n - ans - neut + 1 << endl;
}
