#include <bits/stdc++.h> using namespace std; int main() { ios::sync_with_stdio(false); cin.tie(nullptr); int n, d; cin >> n >> d; vector<vector<int>> adj(n); for (int i = 1, p; i < n; ++i) { cin >> p; adj[p].push_back(i); } auto dfs = [&](auto &&self, int u) -> deque<int> { deque<int> dp(n); for (int &i : adj[u]) { deque<int> ndp = self(self, i); ndp.push_front(0); ndp.pop_back(); deque<int> nndp(n); for (int i = 0; i < ndp.size(); ++i) { nndp[i] = max(dp[i], ndp[i]); } for (int i = 0; i < dp.size(); ++i) { for (int j = 0; j < ndp.size(); ++j) { nndp[min(i, j)] = max(nndp[min(i, j)], dp[i] + ndp[j]); } } dp = nndp; } dp[0] = max(dp[0], dp[d] + 1); return dp; }; deque<int> dp = dfs(dfs, 0); cout << *max_element(dp.begin(), dp.end()) << '\n'; }