#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ll long long
#define pii pair<int,int>
#define F first
#define S second
#define endl '\n'
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(),a.end()
const int mod = 1e9 + 7;
const int N = 1e6 + 15;
const ll inf = 1e12;
vector<int> adj[N];
int d[N], w[N];
map<int,int> mp[N];
int ans = 0;
void dfs(int node){
for (auto to : adj[node]){
dfs(to);
if (sz(mp[to]) > sz(mp[node])){
swap(mp[to], mp[node]);
}
for (auto it : mp[to]){
mp[node][it.F] += it.S;
}
}
int cur = w[node];
while (cur){
auto up = mp[node].upper_bound(d[node]);
int x = min(cur, up->second);
cur -= x;
mp[node][d[node]] += x;
mp[node][up->first] -= x;
if (cur >= up->second){
mp[node].erase(up);
}
}
if (node==1){
for (auto it : mp[node]){
if (it.first == inf) {
break;
}
ans += it.S;
}
}
return;
}
int32_t main(){
ios_base::sync_with_stdio(0);cin.tie(0);
int n, m, k;
cin >> n >> m >> k;
for (int i=1;i<=n;i++) mp[i][inf] = inf;
for (int i=2;i<=n;i++){
int u;
cin >> u;
adj[u].pb(i);
}
for (int i=0;i<m;i++){
int node;
cin >> node;
cin >> d[node] >> w[node];
}
dfs(1);
cout << ans << endl;
}
