#include <iostream>
#include <numeric>
#include <vector>
#include <algorithm>
#include <utility>
#ifndef LOCAL
#include "friend.h"
#endif
template <class T>
using Vec = std::vector<T>;
int findSample(int n, int confidence[], int host[], int protocol[]) {
Vec<int> take(n), ignore(n);
for (int i = 0; i < n; ++i) {
take[i] = confidence[i];
}
for (int i = n - 1; i >= 1; --i) {
const auto u = host[i];
const auto v = i;
const auto p = protocol[i];
if (p == 0) {
const auto tk = take[u] + ignore[v];
const auto ig = ignore[u] + std::max(take[v], ignore[v]);
take[u] = tk;
ignore[u] = ig;
}
else if (p == 1) {
const auto tk = std::max(take[u] + std::max(take[v], ignore[v]), ignore[u] + take[v]);
const auto ig = ignore[u] + ignore[v];
take[u] = tk;
ignore[u] = ig;
}
else {
const auto tk = std::max(take[u] + ignore[v], ignore[u] + take[v]);
const auto ig = ignore[u] + ignore[v];
take[u] = tk;
ignore[u] = ig;
}
}
return std::max(take[0], ignore[0]);
}
#ifdef LOCAL
int main() {
int n;
std::cin >> n;
int cf[100] = {};
for (int i = 0; i < n; ++i) {
std::cin >> cf[i];
}
int host[100] = {};
int prot[100] = {};
for (int i = 1; i < n; ++i) {
std::cin >> host[i] >> prot[i];
}
std::cout << findSample(n, cf, host, prot) << '\n';
return 0;
}
#endif
