/**
____ ____ ____ ____ ____
||a |||t |||o |||d |||o ||
||__|||__|||__|||__|||__||
|/__\|/__\|/__\|/__\|/__\|
**/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N_MAX = 100000;
const int K_MAX = 100000;
int N, M, K;
int parent[N_MAX + 2];
vector <int> sons[N_MAX + 2];
int ripeTime[N_MAX + 2];
ll juice[N_MAX + 2];
struct Fenwick {
map <int, ll> mp;
map <int, ll> upds;
void update (int pos, ll val) {
upds[pos] += val;
for (int i = pos; i <= K; i += i & -i) {
mp[i] += val;
}
}
ll query (int pos) {
ll val = 0;
for (int i = pos; i >= 1; i -= i & -i) {
if (mp.find(i) != mp.end()) {
val += mp[i];
}
}
return val;
}
void maxify (int pos, ll val) {
update(pos, val);
while (val > 0) {
map <int, ll> :: iterator it = upds.lower_bound(pos + 1);
if (it == upds.end()) {
break;
}
int itpos = it->first;
ll itval = it->second;
if (itval <= val) {
update(itpos, -itval);
val -= itval;
upds.erase(itpos);
} else {
update(itpos, -val);
val = 0;
}
}
}
};
Fenwick Fen[K_MAX + 2];
void dfs (int u) {
int heavy = -1;
for (int v : sons[u]) {
dfs(v);
if (heavy == -1 || (int) Fen[heavy].upds.size() < (int) Fen[v].upds.size()) {
heavy = v;
}
}
if (heavy != -1) {
swap(Fen[u], Fen[heavy]);
}
for (int v : sons[u]) {
if (v != heavy) {
for (pair <int, ll> upd : Fen[v].upds) {
Fen[u].update(upd.first, upd.second);
}
Fen[v].upds.clear();
Fen[v].mp.clear();
}
}
if (juice[u] != 0) {
Fen[u].maxify(ripeTime[u], juice[u]);
}
}
int main () {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin >> N >> M >> K;
for (int u = 2; u <= N; u++) {
cin >> parent[u];
sons[parent[u]].push_back(u);
}
for (int i = 1; i <= M; i++) {
int u;
cin >> u;
cin >> ripeTime[u] >> juice[u];
}
dfs(1);
cout << Fen[1].query(K) << "\n";
return 0;
}
