#include <bits/stdc++.h>
using namespace std;
mt19937 rnd(time(0));
bool isPrime(long long a) {
  long long i;
  for (i = 2; i * i <= a; i++) {
    if (a % i == 0) {
      return 0;
    }
  }
  return (a != 1);
}
bool isPalindrom(const string &s, int l, int r) {
  for (int i = 0; i < (r - l + 1) / 2; i++) {
    if (s[l + i] != s[r - i]) {
      return 0;
    }
  }
  return 1;
}
template <class type1>
type1 gcd(type1 a, type1 b) {
  type1 t;
  while (b) {
    t = b;
    b = a % b;
    a = t;
  }
  return a;
}
long long positiveMod(long long v, long long md) {
  v = v % md;
  if (v < 0) {
    v += md;
  }
  return v;
}
int n, m, k;
struct str {
  int l, r;
  long long val;
  str() : l(-1), r(-1), val(0){};
};
class impST {
 public:
  vector<str> st;
  set<int> points;
  long long getSum(int v, int l, int r, int tl, int tr) {
    if (v == -1) {
      return 0;
    }
    if (tl == l && tr == r) {
      return st[v].val;
    } else {
      int mid = (l + r) / 2;
      if (tr <= mid) {
        return getSum(st[v].l, l, mid, tl, tr);
      } else if (mid < tl) {
        return getSum(st[v].r, mid + 1, r, tl, tr);
      } else {
        return getSum(st[v].l, l, mid, tl, mid) +
               getSum(st[v].r, mid + 1, r, mid + 1, tr);
      }
    }
  }
  void upd(int v, int l, int r, int pos, long long val) {
    if (l == r) {
      st[v].val += val;
    } else {
      if (st[v].l == -1) {
        st[v].l = st.size();
        st.push_back(str());
      }
      if (st[v].r == -1) {
        st[v].r = st.size();
        st.push_back(str());
      }
      int mid = (l + r) / 2;
      if (pos <= mid) {
        upd(st[v].l, l, mid, pos, val);
      } else {
        upd(st[v].r, mid + 1, r, pos, val);
      }
      st[v].val = st[st[v].l].val + st[st[v].r].val;
    }
  }
  void unite(impST *other) {
    for (auto it : other->points) {
      upd(0, 1, k, it, other->getSum(0, 1, k, it, it));
      points.insert(it);
    }
  }
  void addFruit(int time_, long long volume) {
    upd(0, 1, k, time_, volume);
    long long a = volume, b;
    vector<int> toErase;
    auto it = points.upper_bound(time_);
    while (it != points.end() && a > 0) {
      b = getSum(0, 1, k, *it, *it);
      if (b > a) {
        upd(0, 1, k, *it, -a);
        a = 0;
      } else {
        a -= b;
        upd(0, 1, k, *it, -b);
        toErase.push_back(*it);
      }
      it++;
    }
    for (auto itt : toErase) {
      points.erase(points.find(itt));
    }
    points.insert(time_);
  }
  impST() { st.push_back(str()); }
};
impST *inf[100005];
vector<int> child[100005];
pair<int, long long> fruits[100005];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  int a, b, c, i, j;
  cin >> n >> m >> k;
  for (i = 2; i <= n; i++) {
    cin >> a;
    child[a].push_back(i);
  }
  for (i = 0; i < m; i++) {
    cin >> a >> b >> c;
    fruits[a] = {b, c};
  }
  for (i = n; i >= 1; i--) {
    if (child[i].size() == 1) {
      inf[i] = inf[child[i][0]];
    } else {
      inf[i] = new impST;
      for (auto it : child[i]) {
        if (inf[i]->points.size() < inf[it]->points.size()) {
          swap(inf[i], inf[it]);
        }
        inf[i]->unite(inf[it]);
      }
    }
    if (fruits[i].first != 0) {
      inf[i]->addFruit(fruits[i].first, fruits[i].second);
    }
  }
  cout << inf[1]->st[0].val;
  return 0;
}
