#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vll = vector<ll>;
using vvl = vector<vll>;
using pll = pair<ll,ll>;
#define f first
#define s second
#define pb push_back
#define all(v) v.begin(),v.end()
void merge(multiset<pll>& a, multiset<pll>& b){
if(a.size()<b.size())swap(a,b);
for(auto [d,w]:b){
a.insert({d,w});
}
}
void pl(multiset<pll>& a, ll d, ll w){
a.insert({d,w});
while(w>0){
auto it = a.upper_bound({d,1e18});
if(it==a.end())break;
w-=(*it).s;
ll las = (*it).f;
a.erase(it);
if(w<0){
a.insert({las, -w});
w=0;
}
}
}
vvl g;
vll d, w;
vector<multiset<pll>> he;
ll k;
void dfs(ll cur){
for(ll i:g[cur]){
dfs(i);
merge(he[cur], he[i]);
}
if(d[cur]!=-1)pl(he[cur], d[cur], w[cur]);
}
int main(){
ios_base::sync_with_stdio(0);cin.tie(NULL);
ll n, m;
cin >> n >> m >> k;
g = vvl(n);
he = vector<multiset<pll>>(n);
d = w = vll(n, -1);
for(ll p,i = 1; i < n; ++i){
cin >> p;
p--;
g[p].pb(i);
}
for(ll a,b,c,i = 0; i < m; ++i){
cin >> a >> b >> c;
a--;
d[a]=b;
w[a]=c;
}
dfs(0);
ll ans = 0;
for(auto i:he[0])ans += i.s;
cout << ans;
}
