#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define vt vector
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
#define R_EP(i, a, b, s) for (int i = (a); (s) > 0 ? i < (b) : i > (b); i += (s))
#define R_EP1(e) R_EP(i, 0, e, 1)
#define R_EP2(i, e) R_EP(i, 0, e, 1)
#define R_EP3(i, b, e) R_EP(i, b, e, 1)
#define R_EP4(i, b, e, s) R_EP(i, b, e, s)
#define GET5(a, b, c, d, e, ...) e
#define R_EPC(...) GET5(__VA_ARGS__, R_EP4, R_EP3, R_EP2, R_EP1)
#define rep(...) R_EPC(__VA_ARGS__)(__VA_ARGS__)
#define trav(x, a) for (auto x : a)
template<typename T> inline bool umax(T&x, const T& y) { if (x >= y) return false; x = y; return true; }
template<typename T> inline bool umin(T&x, const T& y) { if (x <= y) return false; x = y; return true; }
const int MOD = int(1e9) + 7, naxm = 5000, INF = int(1e9);
int N, M, a[naxm + 5], dp[naxm + 5][naxm + 5], suffix[naxm + 5];
int main() {
ios_base::sync_with_stdio(false), cin.tie(nullptr);
cin >> N >> M;
rep(i, 1, N + 1) cin >> a[i];
rep(i, N + 1) {
rep(j, 5001) dp[i][j] = INF;
}
dp[0][0] = 0;
rep(i, 1, N + 1) {
rep(j, 5002) suffix[j] = INF;
rep(j, 5000, -1, -1) suffix[j] = min(suffix[j + 1], dp[i - 1][j]);
rep(j, 5001) umin(dp[i][j], suffix[max(0, j - M)] + (j != a[i]));
}
int ans = INF;
rep(i, 5001) umin(ans, dp[N][i]);
cout << ans << "\n";
return 0;
}
