#include <bits/stdc++.h>
using namespace std;
const int INF = 2e9 + 10;
const int N = 2e5 + 2;
int fr[1000002];
int aint[4000002];
int lazy[4000002];
int n, m, p;
struct tool {
  int x, y, pref;
  bool operator<(const tool &a) const {
    if (a.x == x) return y < a.y;
    return x < a.x;
  }
} a[N], b[N];
struct monster {
  int x, y, z;
  bool operator<(const monster &a) const {
    if (x == a.x) {
      if (a.y == y) return z < a.z;
      return y < a.y;
    }
    return x < a.x;
  }
} v[N];
int sum[N];
void build(int nod, int l, int r) {
  if (l == r) {
    aint[nod] = fr[l];
    return;
  }
  int mid = (l + r) / 2;
  build(2 * nod, l, mid);
  build(2 * nod + 1, mid + 1, r);
  aint[nod] = max(aint[2 * nod], aint[2 * nod + 1]);
}
void prop(int nod, int l, int r) {
  if (l != r) {
    aint[2 * nod] += lazy[nod];
    aint[2 * nod + 1] += lazy[nod];
    lazy[2 * nod] += lazy[nod];
    lazy[2 * nod + 1] += lazy[nod];
    lazy[nod] = 0;
  }
}
void update(int nod, int l, int r, int a, int b, int val) {
  if (l > r || r < a || l > b) return;
  if (a <= l && r <= b) {
    aint[nod] += val;
    lazy[nod] += val;
    return;
  }
  if (l != r) {
    prop(nod, l, r);
    int mid = (l + r) / 2;
    update(2 * nod, l, mid, a, b, val);
    update(2 * nod + 1, mid + 1, r, a, b, val);
    aint[nod] = max(aint[2 * nod], aint[2 * nod + 1]);
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n >> m >> p;
  for (int i = 1; i <= n; i++) cin >> a[i].x >> a[i].y;
  for (int i = 1; i < 1000001; i++) fr[i] = -INF;
  for (int i = 1; i <= m; i++) {
    int x, y;
    cin >> x >> y;
    fr[x] = max(fr[x], -y);
  }
  for (int i = 1; i <= p; i++) cin >> v[i].x >> v[i].y >> v[i].z;
  sort(a + 1, a + n + 1);
  sort(v + 1, v + p + 1);
  build(1, 1, 1000000);
  int j = 1;
  int ans = INT_MIN;
  for (int i = 1; i <= n; i++) {
    while (j <= p && v[j].x < a[i].x) {
      update(1, 1, 1000000, v[j].y + 1, 1000000, v[j].z);
      j++;
    }
    ans = max(ans, aint[1] - a[i].y);
  }
  cout << ans;
  return 0;
}
