#include <bits/stdc++.h>
#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
using namespace std;
bool replace(std::string& str, const std::string& from, const std::string& to) {
  size_t start_pos = str.find(from);
  if (start_pos == std::string::npos) return false;
  str.replace(start_pos, from.length(), to);
  return true;
}
inline int c(string& b) {
  int w = 0;
  for (auto& c : b) w = w * 10 + c - '0';
  return w;
}
struct segtree {
  vector<int> t;
  vector<int> a;
  int o = 0, iv = -2e9, ee;
  int _func(int v, int vv) { return max(v, vv); }
  int func(int v1, int v2) { return _func(t[v1], t[v2]); }
  void build(vector<int>& v, int y = -2e9) {
    int x = 1;
    iv = y;
    while (x < v.size()) x <<= 1;
    x *= 2;
    t.resize(x);
    ee = x;
    o = x >> 1;
    while (v.size() < o) v.push_back(y);
    for (int i = 0; i < o; i++) t[i + o] = v[i];
    for (int i = o - 1; i > 0; i--) t[i] = func(i * 2, i * 2 + 1);
    a.resize(x);
  }
  void push(int v) {
    if (a[v]) {
      int v1 = v * 2;
      int v2 = v * 2 + 1;
      t[v] += a[v];
      if (v1 < ee) {
        if (v1 > o)
          t[v1] += a[v];
        else
          a[v1] += a[v];
      }
      if (v2 < ee) {
        if (v2 > o)
          t[v2] += a[v];
        else
          a[v2] += a[v];
      }
      a[v] = 0;
    }
  }
  void _add(int v, int l, int r, int vl, int vr, int w) {
    if (vl > vr) return;
    if (l > vr || r < vl) return;
    if (vl == vr && l <= vl && vr <= r) {
      t[v] += w;
      return;
    }
    if (l <= vl && vr <= r) {
      a[v] += w;
      return;
    }
    push(v);
    int m = (vl + vr) >> 1;
    _add(v << 1, l, r, vl, m, w);
    _add(1 + (v << 1), l, r, m + 1, vr, w);
    if (vl != vr)
      t[v] = _func(t[v << 1] + a[v << 1], t[v * 2 + 1] + a[v * 2 + 1]);
  }
  void add(int l, int r, int v) { _add(1, l, r, 0, o - 1, v); }
  int q(int v, int l, int r, int vl, int vr) {
    if (vl > vr) return iv;
    if (l > vr || r < vl) return iv;
    push(v);
    if (vl != vr)
      t[v] = _func(t[v * 2] + a[v * 2], t[v * 2 + 1] + a[v * 2 + 1]);
    if (l <= vl && vr <= r) return a[v] + t[v];
    int m = (vl + vr) / 2;
    return _func(q(v * 2, l, r, vl, m), q(v * 2 + 1, l, r, m + 1, vr));
  }
  int query(int l, int r) { return q(1, l, r, 0, o - 1); }
};
int32_t main(int32_t argc, char** argv) {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int n, m, p;
  cin >> n >> m >> p;
  vector<pair<int, int>> a(n), b(m);
  vector<pair<int, pair<int, int>>> y(p);
  for (auto& e : a) cin >> e.first >> e.second;
  for (auto& e : b) cin >> e.first >> e.second;
  for (auto& e : y) cin >> e.first >> e.second.first >> e.second.second;
  sort(a.begin(), a.end());
  sort(b.begin(), b.end());
  sort(y.begin(), y.end());
  vector<int> s(m);
  for (int i = 0; i < m; i++) s[i] = -b[i].second;
  int i1 = 0;
  segtree t;
  t.build(s, -2e9);
  int r = -2e9;
  for (int i = 0; i < n; i++) {
    while (i1 < y.size() && y[i1].first < a[i].first) {
      pair<int, int> a = {y[i1].second.first + 1, -2e9};
      auto e = upper_bound(b.begin(), b.end(), a);
      int mx = (e - b.begin());
      if (mx < m) {
        t.add(mx, m - 1, y[i1].second.second);
      }
      i1++;
    }
    r = max(r, t.query(0, m - 1) - a[i].second);
  }
  cout << r;
}
