#include <bits/stdc++.h> using namespace std; typedef long long ll; typedef pair<ll, ll> pll; const ll LOG = 31; const ll MOD = 1000000007; const ll inf = 1e17; const ll B = 2305843009213693951; #define db(x) cerr << #x << " = " << x << " | " #define dbg(x) cerr << #x << " = " << x << "\n" #define Algerian ios::sync_with_stdio(0); #define OI cin.tie(NULL); int main() { Algerian OI ll n, k; cin >> n >> k; vector<ll> a(n), p(n); vector<vector<ll>> ch(n); for (ll i = 0; i < n; i++) cin >> a[i]; for (ll i = 0; i < n; i++) { cin >> p[i]; if (p[i] != -1) ch[p[i]].push_back(i); } vector<vector<ll>> freq(n, vector<ll>(k)); vector<ll> dep(n, -1); dep[0] = 0; auto tmp = [&](ll x, auto&& tmp) -> ll { return (dep[x] == -1 ? dep[x] = tmp(p[x], tmp) + 1 : dep[x]); }; for (ll i = 0; i < n; i++) { dep[i] = tmp(p[i], tmp); freq[dep[i]][a[i]]++; } ll res = 0; vector<ll> d(n); auto dfs = [&](ll u, auto&& dfs) -> void { d[dep[u]]++; for (ll v : ch[u]) { dfs(v, dfs); } }; for (ll i = 0; i < n; i++) { for (ll& x : d) x = 0; dfs(i, dfs); ll h = 0; for (ll j = 0; j < n; j++) { h += min(freq[j][a[i]], d[i]); } res = max(res, h); } cout << res << "\n"; return 0; }