#include <bits/stdc++.h>
using namespace std;
long long n, m, p;
struct node {
  long long val, x, y;
} a[200010], b[200010], c[200010];
long long sum[800010], tag[800010], tmp[200010];
struct FastIO {
  static const long long S = 1048576;
  char buf[S], *L, *R;
  long long stk[20], Top;
  ~FastIO() { clear(); }
  inline char nc() {
    return L == R && (R = (L = buf) + fread(buf, 1, S, stdin), L == R) ? EOF
                                                                       : *L++;
  }
  inline void clear() {
    fwrite(buf, 1, Top, stdout);
    Top = 0;
  }
  inline void pc(char ch) {
    Top == S && (clear(), 0);
    buf[Top++] = ch;
  }
  inline void endl() { pc('\n'); }
  FastIO& operator>>(long long& ret) {
    ret = 0;
    long long f = 1;
    char ch = nc();
    while (ch < '0' || ch > '9') {
      if (ch == '-') f = -f;
      ch = nc();
    }
    while (ch >= '0' && ch <= '9') {
      ret = ret * 10 + ch - '0';
      ch = nc();
    }
    ret *= f;
    return *this;
  }
  FastIO& operator>>(char* s) {
    register long long Len = 0;
    register char ch = nc();
    while (ch != '\n') {
      *(s + Len) = ch;
      Len++;
      ch = nc();
    }
  }
  FastIO& operator<<(long long x) {
    if (x < 0) {
      pc('-');
      x = -x;
    }
    do {
      stk[++stk[0]] = x % 10;
      x /= 10;
    } while (x);
    while (stk[0]) pc('0' + stk[stk[0]--]);
    return *this;
  }
  FastIO& operator<<(char ch) {
    pc(ch);
    return *this;
  }
  FastIO& operator<<(string str) {
    register long long Len = str.size() - 1;
    for (stk[0] = 0; Len >= 0; Len--) stk[++stk[0]] = str[Len];
    while (stk[0]) pc(stk[stk[0]--]);
    return *this;
  }
} fin, fout;
bool cmp(node a, node b) { return a.x < b.x; }
void update(long long x) { sum[x] = max(sum[x * 2], sum[x * 2 + 1]); }
void pushdown(long long x) {
  if (!tag[x]) return;
  sum[x * 2] += tag[x], sum[x * 2 + 1] += tag[x];
  tag[x * 2] += tag[x], tag[x * 2 + 1] += tag[x];
  tag[x] = 0;
}
void modify(long long x, long long l, long long r, long long ql, long long qr,
            long long k) {
  if (l >= ql && r <= qr) {
    sum[x] += k, tag[x] += k;
    return;
  }
  long long mid = l + r >> 1;
  pushdown(x);
  if (mid >= ql) modify(x * 2, l, mid, ql, qr, k);
  if (mid < qr) modify(x * 2 + 1, mid + 1, r, ql, qr, k);
  update(x);
}
void init() {
  fin >> n >> m >> p;
  for (long long i = 1; i <= n; i++) fin >> a[i].x >> a[i].val;
  for (long long i = 1; i <= m; i++) fin >> b[i].x >> b[i].val;
  for (long long i = 1; i <= p; i++) fin >> c[i].x >> c[i].y >> c[i].val;
  sort(a + 1, a + n + 1, cmp), sort(b + 1, b + m + 1, cmp),
      sort(c + 1, c + p + 1, cmp);
  for (long long i = 1; i <= m; i++)
    tmp[i] = b[i].x, modify(1, 1, m, i, i, -b[i].val);
}
void doit() {
  long long j = 1, i = 1, ans = -99999999999999;
  while (i <= n) {
    while (a[i].x > c[j].x && j <= p) {
      long long k = upper_bound(tmp + 1, tmp + m + 1, c[j].y) - tmp;
      if (k <= m) modify(1, 1, m, k, m, c[j].val);
      j++;
    }
    ans = max(ans, sum[1] - a[i].val);
    i++;
  }
  fout << ans << '\n';
}
int main() {
  init();
  doit();
  return 0;
}
