#include<bits/stdc++.h>
#define int long long
using namespace std;
multiset<pair<int, int>> st[100005];
void unite(int u, int v)
{
if(st[u].size() < st[v].size()) st[u].swap(st[v]);
for(auto i : st[v]) st[u].insert(i);
}
vector<int> ad[100005];
int d[100005], w[100005];
void dfs(int u)
{
st[u].insert(make_pair(1e18, 1e18));
for(int v : ad[u]){
dfs(v); unite(u, v);
}
/*cerr<<"A"<<u<<endl;
for(auto i : st[u]) cerr<<i.first<<" "<<i.second<<endl;
cerr<<endl;*/
//Now add
if(w[u] == 0) return;
int sum = 0;
multiset<pair<int, int>>::iterator it = st[u].lower_bound(make_pair(d[u], -1));
while(true){
if((*it).second + sum > w[u]){
pair<int, int> target = *it;
target.second -= w[u] - sum;
st[u].erase(it);
st[u].insert(target); break;
}
sum += (*it).second; st[u].erase(it++);
}
st[u].insert(make_pair(d[u], w[u]));
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
int n, m, day; cin>>n>>m>>day;
for(int i = 2; i <= n; i++){
int p; cin>>p; ad[p].push_back(i);
}
for(int i = 1; i <= m; i++){
int u; cin>>u; cin>>d[u]>>w[u];
}
dfs(1);
int ans = 0;
for(auto i : st[1]) if(i.first <= day) ans += i.second;
cout<<ans;
}
