#include <bits/stdc++.h>
using namespace std;
#define all(x) x.begin(), x.end()
#define ar array
#define pb push_back
#define ln '\n'
#define int long long
using i64 = long long;
template <class F, class _S>
bool chmin(F &u, const _S &v){
bool flag = false;
if ( u > v ){
u = v; flag |= true;
}
return flag;
}
template <class F, class _S>
bool chmax(F &u, const _S &v){
bool flag = false;
if ( u < v ){
u = v; flag |= true;
}
return flag;
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int n, m, k; cin >> n >> m >> k;
vector <vector<int>> G(n);
for ( int i = 1; i < n; i++ ){
int p; cin >> p;
--p;
G[p].pb(i);
}
vector <int> w(n), d(n);
for ( int i = 0; i < m; i++ ){
int d_, v, w_; cin >> v >> d_ >> w_;
--v;
w[v] = w_;
d[v] = d_;
}
int opt = 0;
for ( int mask = 0; mask < 1 << n; mask++ ){
vector <int> dp(n);
int cnt = 0;
for ( int i = 0; i < n; i++ ){
if ( mask >> i & 1 ){
dp[i] = d[i];
cnt += w[i];
}
}
auto dfs = [&](auto dfs, int u) -> bool{
bool ret = true;
int mx = 0;
for ( auto &v: G[u] ){
ret &= dfs(dfs, v);
chmax(mx, dp[v]);
}
if ( mx > dp[u] && (mask >> u & 1)){
ret = false;
}
chmax(dp[u], mx);
return ret;
};
chmax(opt, dfs(dfs, 0) * cnt);
}
cout << opt;
cout << '\n';
}
