#include <bits/stdc++.h>
#define FASTIO
using namespace std;

using ll = long long;
using Vi = vector<int>;
using Vl = vector<ll>;
using Pii = pair<int, int>;
using Pll = pair<ll, ll>;

constexpr int I_INF = numeric_limits<int>::max();
constexpr ll L_INF = numeric_limits<ll>::max();

template <typename T1, typename T2>
bool chmin(T1& a, const T2& b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template <typename T1, typename T2>
bool chmax(T1& a, const T2& b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

class Prints {
private:
    class __Prints {
    public:
        __Prints(const char* sep, const char* term) : sep(sep), term(term) {}
        template <class... Args>
        void operator()(const Args&... args) const { print(args...); }

    private:
        const char *sep, *term;
        void print() const { std::cout << term; }
        void print_rest() const { std::cout << term; }
        template <class T, class... Tail>
        void print(const T& head, const Tail&... tail) const { std::cout << head, print_rest(tail...); }
        template <class T, class... Tail>
        void print_rest(const T& head, const Tail&... tail) const { std::cout << sep << head, print_rest(tail...); }
    };

public:
    Prints() {}
    __Prints operator()(const char* sep = " ", const char* term = "\n") const { return __Prints(sep, term); }
};

Prints prints;

//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

template <class T, class Op>
class SegmentTree {
private:
    const Op op;
    const T id;
    std::vector<T> vec;
    int sz;

public:
    explicit SegmentTree(int n, Op op, T id) noexcept
        : op(op), id(id) {
        sz = 1;
        while (sz < n) sz <<= 1;
        vec.assign(sz * 2, id);
    }
    explicit SegmentTree(const std::vector<T>& vec, Op op, T id) noexcept
        : op(op), id(id) {
        int n = vec.size();
        sz = 1;
        while (sz < n) sz <<= 1;
        this->vec.assign(sz * 2, id);
        set_array(vec);
    }
    void set_value(int idx, T val) noexcept {
        vec[idx + sz] = val;
    }
    template <class RandomIt>
    void set_array(RandomIt _begin, RandomIt _end) noexcept {
        std::copy(_begin, _end, vec.begin() + sz);
    }
    void set_array(const std::vector<T>& vec) noexcept {
        set_array(vec.begin(), vec.end());
    }
    void build() noexcept {
        for (int i = sz - 1; i > 0; i--) {
            vec[i] = op(vec[i * 2], vec[i * 2 + 1]);
        }
    }
    void update(int idx, T val) noexcept {
        idx += sz;
        vec[idx] = val;
        for (idx >>= 1; idx > 0; idx >>= 1) {
            vec[idx] = op(vec[idx * 2], vec[idx * 2 + 1]);
        }
    }
    // Query [l, r)
    T query(int l, int r) const noexcept {
        T l_val = id, r_val = id;
        l += sz, r += sz - 1;
        for (; l <= r; l >>= 1, r >>= 1) {
            if (l & 1) l_val = op(l_val, vec[l++]);
            if (!(r & 1)) r_val = op(r_val, vec[r--]);
        }
        return op(l_val, r_val);
    }
    const T& operator[](int idx) const noexcept {
        return vec[idx + sz];
    }
    void reset() noexcept {
        std::fill(vec.begin(), vec.end(), id);
    }
};

void solve() {
    ll H, W, M;
    cin >> H >> W >> M;
    map<ll, Vi> xs;
    map<ll, ll> ys;
    for (ll i = 0; i < M; i++) {
        int a, b;
        cin >> a >> b;
        --a, --b;
        xs[a].emplace_back(b);
        ++ys[b];
    }

    ll sz = (ll)ys.size();
    map<ll, ll> pos;
    Vl vals;
    for (auto [a, b] : ys) {
        vals.emplace_back(b);
        pos[a] = (ll)vals.size() - 1;
    }

    auto op = [](ll l, ll r) { return max(l, r); };
    SegmentTree seg(sz, op, 0ll);
    for (ll i = 0; i < sz; i++) {
        seg.set_value(i, vals[i]);
    }
    seg.build();

    ll ans = 0;
    for (const auto& [a, vec] : xs) {
        ll t = (ll)vec.size();
        for (auto b : vec) {
            ll idx = pos[b];
            ll v = seg[idx];
            seg.update(idx, v - 1);
        }
        chmax(ans, t + seg.query(0, sz));
        for (auto b : vec) {
            ll idx = pos[b];
            ll v = seg[idx];
            seg.update(idx, v + 1);
        }
    }
    prints()(ans);
}

//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

int main() {
#ifdef FASTIO
    cin.tie(0), cout.tie(0);
    ios::sync_with_stdio(false);
#endif
#ifdef FILEINPUT
    ifstream ifs("./in_out/input.txt");
    cin.rdbuf(ifs.rdbuf());
#endif
#ifdef FILEOUTPUT
    ofstream ofs("./in_out/output.txt");
    cout.rdbuf(ofs.rdbuf());
#endif
    cout << setprecision(18) << fixed;
    solve();
    cout << flush;
    return 0;
}

Measured memory_bytes: 84128