#include <bits/stdc++.h>
using namespace std;
#define BIT(n) (1LL << (n))
#define BITF(n, i) (((n) >> (i)) & 1)
#define REP(i, n) for (int i = 0; i < n; i++)
#define FOR(i, m, n) for (int i = m; i < n; i++)
#define REPI(i, x) for (int i = 1; i <= x; i++)
#define FORI(i, m, n) for (int i = m; i <= n; i++)
#define REPR(i, n) for (int i = n; i >= 0; i--)
#define REPZ(i, x) for (int i = 0; i <= x; i++)
#define FORA(i, n) for (auto &&i : n)
#define POW(a, b) ((int)(pow(a, b) + .5))
#define MODULO(a, b) (((a) % (b)) < 0 ? (a) % (b) + (b) : (a) % (b))
#define DUMPOUT cerr
// vector
template <typename T> istream &operator>>(istream &is, vector<T> &vec) {
  for (T &x : vec) is >> x;
  return is;
}
// pair
template <typename T, typename U> ostream &operator<<(ostream &os, pair<T, U> &pair_var) {
  os << "(" << pair_var.first << ", " << pair_var.second << ")";
  return os;
}
// vector
template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
  os << "{";
  REP(i, (int)vec.size())
  os << vec[i] << (i + 1 == (int)vec.size() ? "" : ", ");
  os << "}";
  return os;
}
// map
template <typename T, typename U> ostream &operator<<(ostream &os, map<T, U> &map_var) {
  os << "{";
  FORA(itr, map_var) {
    os << *itr;
    itr++;
    if (itr != map_var.end()) os << ", ";
    itr--;
  }
  os << "}";
  return os;
}
// set
template <typename T> ostream &operator<<(ostream &os, set<T> &set_var) {
  os << "{";
  FORA(itr, set_var) {
    os << *itr;
    itr++;
    if (itr != set_var.end()) os << ", ";
    itr--;
  }
  os << "}";
  return os;
}
void dump_func() { DUMPOUT << endl; }
template <class Head, class... Tail> void dump_func(Head &&head, Tail &&... tail) {
  DUMPOUT << head;
  if (sizeof...(Tail) > 0) DUMPOUT << ", ";
  dump_func(std::move(tail)...);
}
#ifdef DEBUG_
#define DEB
#define DUMP(...)                                                             \
  DUMPOUT << "  " << string(#__VA_ARGS__) << ": "                             \
          << "[" << to_string(__LINE__) << ":" << __FUNCTION__ << "]" << endl \
          << "    ",                                                          \
      dump_func(__VA_ARGS__)
#define PRINTARR(x, y)                                     \
  cerr << #x << "=\n";                                     \
  for (auto itr = x; itr != y; itr++) cerr << *itr << " "; \
  cerr << endl;
#define PRINTARR2(x, i0, i1)                                       \
  cerr << #x << "=\n";                                             \
  for (int ii0 = 0; ii0 < i0; ii0++) {                             \
    for (int ii1 = 0; ii1 < i1; ii1++) cerr << x[ii0][ii1] << " "; \
    cerr << endl;                                                  \
  }
#else
#define DEB if (false)
#define DUMP(...)
#define PRINTARR(x, y)
#define PRINTARR2(x, i0, i1)
#endif
#define ALL(v) v.begin(), v.end()
#define fst first
#define snd second
#define mp make_pair
#define pb push_back
#define epb emplace_back
#define int long long
#define pint pair<int, int>
#define pdouble pair<double, double>
#define ld long double
using namespace std;
template <class T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> bool chmin(T &a, const T &b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> using vec = std::vector<T>;
template <class T> void print(const T &x) { cout << x << "\n"; }
const int MOD = 1000000007, INF0 = 1061109567, INF = INF0 * INF0;
const double EPS = 1e-7, PI = acos(-1.0);
const int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
/*
[&] { return; }();下のスラッシュを2つ追加しただけ.上のスラッシュを2つにすれば外れる.
//*/
#define MAXN 300100
int cntH[MAXN];
int cntW[MAXN];
map<pint, int> ma;
vec<pint> lisW;
vec<pint> lisH;
typedef tuple<int, int, int> i3;
priority_queue<i3> que;
signed main() {
  cin.tie(0), ios::sync_with_stdio(false);
  cout << fixed << setprecision(12);
  int H, W, M;
  cin >> H >> W >> M;
  REP(i, M) {
    int p, q;
    cin >> p >> q;
    p--, q--;

    cntH[p]++;
    cntW[q]++;
    ma[mp(p, q)]++;
  }

  REP(i, H) lisH.pb(mp(cntH[i], i));
  REP(i, W) lisW.pb(mp(cntW[i], i));
  sort(ALL(lisH));
  reverse(ALL(lisH));
  sort(ALL(lisW));
  reverse(ALL(lisW));
  //  REP(i, H) { rankH[i] = lisH[i].snd; }
  int ans = 0;
  int tmp = lisH[0].fst + lisW[0].fst;
  que.push(make_tuple(tmp, 0, 0));
  map<pint, int> flg;
  //  int counter=0;
  while (1) {
    auto ele = que.top();
    int v0 = get<0>(ele);
    int v1 = get<1>(ele);
    int v2 = get<2>(ele);
    DUMP(v0, v1, v2);
    que.pop();
    if (ma[mp(lisH[v1].snd, lisW[v2].snd)] == 0) {
      chmax(ans, v0);
      break;
    } else {
      chmax(ans, v0 - 1);
    }
    if (v1 + 1 < H && v2 < W && flg[mp(v1 + 1, v2)] == 0) {
      flg[mp(v1 + 1, v2)] = 1;
      que.push(make_tuple(lisH[v1 + 1].fst + lisW[v2].fst, v1 + 1, v2));
    }
    if (v1 < H && v2 + 1 < W && flg[mp(v1, v2 + 1)] == 0) {
      flg[mp(v1, v2 + 1)] = 1;
      que.push(make_tuple(lisH[v1].fst + lisW[v2 + 1].fst, v1, v2 + 1));
    }
    if (que.size() == 0) break;
    // if (que.size())
  }
  print(ans);
}

Measured memory_bytes: 59488