#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 10;
struct node {
  node(long long _v = 0, long long _c = 0) : v(_v), c(_c) {}
  long long v, c;
} a[N], b[N];
struct node1 {
  long long x, y, z;
} c[N];
struct seg_tree {
  long long tree[N << 2], lazy[N << 2];
  void build(int l, int r, int x) {
    if (l == r) {
      tree[x] = -b[l].c;
      return;
    }
    int mid = (l + r) >> 1;
    build(l, mid, x << 1);
    build(mid + 1, r, x << 1 | 1);
    tree[x] = max(tree[x << 1], tree[x << 1 | 1]);
  }
  void add(int st, int ed, int l, int r, int x, int c) {
    if (st <= l && r <= ed) {
      lazy[x] += c;
      tree[x] += c;
      return;
    }
    if (lazy[x]) {
      tree[x << 1 | 1] += lazy[x];
      tree[x << 1] += lazy[x];
      lazy[x << 1 | 1] += lazy[x];
      lazy[x << 1] += lazy[x];
      lazy[x] = 0;
    }
    int mid = (l + r) >> 1;
    if (st <= mid) add(st, ed, l, mid, x << 1, c);
    if (ed > mid) add(st, ed, mid + 1, r, x << 1 | 1, c);
    tree[x] = max(tree[x << 1], tree[x << 1 | 1]);
  }
} seg;
bool cmp(const node &l, const node &r) {
  return l.v == r.v ? l.c < r.c : l.v < r.v;
}
int main() {
  ios::sync_with_stdio(false);
  int n, m, p;
  cin >> n >> m >> p;
  for (int i = 1; i <= n; i++) cin >> a[i].v >> a[i].c;
  for (int i = 1; i <= m; i++) cin >> b[i].v >> b[i].c;
  sort(a + 1, a + n + 1, cmp);
  sort(b + 1, b + m + 1, cmp);
  seg.build(1, m, 1);
  for (int i = 1; i <= p; i++) cin >> c[i].x >> c[i].y >> c[i].z;
  sort(c + 1, c + p + 1, [](const node1 &l, const node1 &r) {
    return l.x == r.x ? l.y < r.y : l.x < r.x;
  });
  long long ans = -9e18;
  for (int i = 1, j = 1; i <= n; i++) {
    if (a[i].v == a[i - 1].v) continue;
    while (j <= p && c[j].x < a[i].v) {
      int k = upper_bound(b + 1, b + m + 1, node(c[j].y, 9e18), cmp) - b;
      if (k <= m) seg.add(k, m, 1, m, 1, c[j].z);
      j++;
    }
    ans = max(ans, seg.tree[1] - a[i].c);
  }
  cout << ans;
}
