#include <bits/stdc++.h>
#include <atcoder/scc>
using namespace std;
using namespace atcoder;
using ll = long long;


vector<vector<int> > get_DAG_from_SCC(int n, vector<ll>& a, vector<ll>& b, vector<vector<int> >& graph, vector<vector<int> >& scc) {
    int sz = (int)scc.size();
    vector<ll> p(sz), q(sz);

    vector<vector<int> > dag(sz, vector<int>({}));
    vector<int> group(n);
    for (int i = 0; i < sz; i++) {
        for (int x : scc[i]) {
            group[x] = i;
            p[i] += a[x];    q[i] += b[x];
        }
    }
    a = p;    b = q;

    for (int i = 0; i < n; i++) {
        for (int k : graph[i]) {
            int x = group[i], y = group[k];
            if (x != y) {
                dag[x].push_back(y);
            }
        }
    }
    for (vector<int>& vec : dag) {
        sort(vec.begin(), vec.end());
        vec.erase(unique(vec.begin(), vec.end()), vec.end());
    }

    return dag;
}


ll get_dp(ll mid, int n, vector<ll>& a, vector<ll>& b, vector<vector<int> >& dag, vector<bool>& visited, int v) {
    visited[v] = true;
    ll ret = a[v] - b[v] * mid;
    for (int x : dag[v]) {
        ret += get_dp(mid, n, a, b, dag, visited, x);
    }
    return min(ret, 0ll);
}


bool check(ll mid, int n, vector<ll>& a, vector<ll>& b, vector<vector<int> >& dag) {
    vector<bool> visited(n);
    for (int v_start = 0; v_start < n; ++v_start) {
        if (visited[v_start] || get_dp(mid, n, a, b, dag, visited, v_start) == 0) {
            continue;
        }
        return false;
    }
    return true;
}


int main(void) {
    int n;    cin >> n;
    vector<ll> a(n), b(n);
    vector<int> c(n);
    ll sa = 0, sb = 0;
    for(auto& x : a){
        cin >> x;    sa += x;
    }
    for(auto& x : b){
        cin >> x;    sb += x;
    }
    for(auto& x : c){
        cin >> x;    --x;
    }

    vector<vector<int> > graph(n, vector<int>({}));
    scc_graph g(n);
    for (int i = 0; i < n; ++i) {
        if (i == c[i]) {
            continue;
        }
        graph[c[i]].push_back(i);
        g.add_edge(c[i], i);
    }
    vector<vector<int> > scc = g.scc();
    vector<vector<int> > dag = get_DAG_from_SCC(n, a, b, graph, scc);
    n = (int)scc.size();

    ll ok = 0;
    ll ng = sa / sb + 1;
    while (abs(ok - ng) > 1) {
        ll mid = (ok + ng) >> 1;
        if (check(mid, n, a, b, dag)) {
            ok = mid;
        }
        else {
            ng = mid;
        }
    }
    cout << ok << endl;

    return 0;
}