Problem p02580 (C++) — buggy submission, verdict: Time Limit Exceeded

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

// エイリアス
using ll = long signed long;
using ull = long unsigned long;
using ld = long double;
using P = pair<int, int>;
using llP = pair<ll, ll>;
using DoP = pair<double, double>;

// 汎用マクロ
#define ALL(a) (a).begin(), (a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define rep(i, n) for (int i = 0; i < n; ++i)
#define FOREACH(i, q) for (auto &i : q)
#define UNIQUE(v)                                                              \\
  do {                                                                         \\
    sort((v).begin(), (v).end());                                              \\
    (v).erase(unique((v).begin(), (v).end()), (v).end());                      \\
  } while (false)
#define SZ(x) ((int)(x).size())
template <class T> inline bool chmin(T &a, const T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline bool chmax(T &a, const T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline void line_out(const vector<T> vec) {
  int n = SZ(vec);
  rep(i, n) {
    cout << vec[i];
    if (i < n - 1)
      cout << " ";
  }
  cout << endl;
}
const int di[] = {0, 1, 0, -1, 1, 1, -1, -1};
const int dj[] = {1, 0, -1, 0, 1, -1, 1, -1};
const int INF = 1 << 28;
const ll INF64 = 1ll << 55;
const int mod = 1000000007;
// const int mod = 998244353;
struct mint {
  ll x; // typedef long long ll;
  mint(ll x = 0) : x((x % mod + mod) % mod) {}
  mint operator-() const { return mint(-x); }
  mint &operator+=(const mint a) {
    if ((x += a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator-=(const mint a) {
    if ((x += mod - a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const {
    mint res(*this);
    return res += a;
  }
  mint operator-(const mint a) const {
    mint res(*this);
    return res -= a;
  }
  mint &operator++() {
    if ((x += 1) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator--() {
    if ((x += mod - 1) >= mod)
      x -= mod;
    return *this;
  }
  mint operator*(const mint a) const {
    mint res(*this);
    return res *= a;
  }
  mint pow(ll t) const {
    if (!t)
      return 1;
    mint a = pow(t >> 1);
    a *= a;
    if (t & 1)
      a *= *this;
    return a;
  }

  // for prime mod
  mint inv() const { return pow(mod - 2); }
  mint &operator/=(const mint a) { return (*this) *= a.inv(); }
  mint operator/(const mint a) const {
    mint res(*this);
    return res /= a;
  }
};

int main() {
  int h, w, m;
  cin >> h >> w >> m;
  vector<P> point(m);
  vector<int> hv(h, 0), wv(w, 0);
  rep(i, m) {
    int x, y;
    cin >> x >> y;
    --x;
    --y;
    point[i] = make_pair(x, y);
    ++hv[x];
    ++wv[y];
  }
  sort(ALL(point));

  vector<P> hp(h);
  vector<P> wp(w);
  rep(i, h) hp[i] = make_pair(hv[i], i);
  rep(i, w) wp[i] = make_pair(wv[i], i);
  sort(ALL(hp));
  sort(ALL(wp));

  int max_h = hp.back().first;
  int max_w = wp.back().first;

  int ans = max_h + max_w - 1;

  for (auto it1 = lower_bound(ALL(hp), make_pair(max_h, 0)); it1 != hp.end();
       ++it1) {
    for (auto it2 = lower_bound(ALL(wp), make_pair(max_w, 0)); it2 != wp.end();
         ++it2) {
      int tmp = max_h + max_w - 1;
      int i = it1->second;
      int j = it2->second;
      if (!binary_search(ALL(point), P(i, j))) {
        cout << ans + 1 << endl;
        return 0;
      }
    }
  }
  cout << ans << endl;
}


Error: TLE

Fixed submission:

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

// エイリアス
using ll = long signed long;
using ull = long unsigned long;
using ld = long double;
using P = pair<int, int>;
using llP = pair<ll, ll>;
using DoP = pair<double, double>;

// 汎用マクロ
#define ALL(a) (a).begin(), (a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define rep(i, n) for (int i = 0; i < n; ++i)
#define FOREACH(i, q) for (auto &i : q)
#define UNIQUE(v)                                                              \\
  do {                                                                         \\
    sort((v).begin(), (v).end());                                              \\
    (v).erase(unique((v).begin(), (v).end()), (v).end());                      \\
  } while (false)
#define SZ(x) ((int)(x).size())
template <class T> inline bool chmin(T &a, const T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline bool chmax(T &a, const T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline void line_out(const vector<T> vec) {
  int n = SZ(vec);
  rep(i, n) {
    cout << vec[i];
    if (i < n - 1)
      cout << " ";
  }
  cout << endl;
}
const int di[] = {0, 1, 0, -1, 1, 1, -1, -1};
const int dj[] = {1, 0, -1, 0, 1, -1, 1, -1};
const int INF = 1 << 28;
const ll INF64 = 1ll << 55;
const int mod = 1000000007;
// const int mod = 998244353;
struct mint {
  ll x; // typedef long long ll;
  mint(ll x = 0) : x((x % mod + mod) % mod) {}
  mint operator-() const { return mint(-x); }
  mint &operator+=(const mint a) {
    if ((x += a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator-=(const mint a) {
    if ((x += mod - a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const {
    mint res(*this);
    return res += a;
  }
  mint operator-(const mint a) const {
    mint res(*this);
    return res -= a;
  }
  mint &operator++() {
    if ((x += 1) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator--() {
    if ((x += mod - 1) >= mod)
      x -= mod;
    return *this;
  }
  mint operator*(const mint a) const {
    mint res(*this);
    return res *= a;
  }
  mint pow(ll t) const {
    if (!t)
      return 1;
    mint a = pow(t >> 1);
    a *= a;
    if (t & 1)
      a *= *this;
    return a;
  }

  // for prime mod
  mint inv() const { return pow(mod - 2); }
  mint &operator/=(const mint a) { return (*this) *= a.inv(); }
  mint operator/(const mint a) const {
    mint res(*this);
    return res /= a;
  }
};

int main() {
  int h, w, m;
  cin >> h >> w >> m;
  vector<P> point(m);
  vector<int> hv(h, 0), wv(w, 0);
  rep(i, m) {
    int x, y;
    cin >> x >> y;
    --x;
    --y;
    point[i] = make_pair(x, y);
    ++hv[x];
    ++wv[y];
  }
  sort(ALL(point));

  int ans = 0;

  rep(i, h) rep(j, w) {
    int count = hv[i] + wv[j];
    if (binary_search(ALL(point), P(i, j)))
      --count;
    chmax(ans, count);
  }
  cout << ans << endl;
}