#include <bits/stdc++.h>
using namespace std;
#define int long long
using ld = long double;
using pr = pair<int, int>;
#define pb push_back
#define ff first
#define ss second
using vv = vector<vector<int>>;
const int INF = 1e18+1, MOD = 1e9+7, MAXN = 4e5+5, MAXA = 41;
void solve() {
int n, m;
cin >> n >> m;
vector<int> a(n+2, 0);
for (int i = 1; i <= n; i++) cin >> a[i];
vector<int> dp(n+1, INF);
dp[0] = 0;
for (int i = 1; i <= n; i++) {
if (a[i] > m * i) continue;
for (int j = 0; j < i; j++) {
if ((i - j) * m + a[j] >= a[i])
dp[i] = min(dp[i], dp[j] + (i - j - 1));
}
}
cout << min({dp[n], dp[n-1]+1, n});
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
// int T;
// cin >> T;
// while (T--)
solve();
}
