Problem p02580 (C++)

Buggy submission (status: Time Limit Exceeded):
/**
 *    author:  otera
 **/
#include <algorithm>
#include <bitset>
#include <cassert>
#include <ciso646>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstring>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;

// #define int long long
typedef long long ll;
typedef unsigned long long ul;
typedef unsigned int ui;
typedef long double ld;
const int inf = 1e9 + 7;
const ll INF = 1LL << 60;
const ll mod = 1e9 + 7;
#define rep(i, n) for (int i = 0; i < n; i++)
#define per(i, n) for (int i = n - 1; i >= 0; i--)
#define Rep(i, sta, n) for (int i = sta; i < n; i++)
#define rep1(i, n) for (int i = 1; i <= n; i++)
#define per1(i, n) for (int i = n; i >= 1; i--)
#define Rep1(i, sta, n) for (int i = sta; i <= n; i++)
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<int, int> P;
typedef pair<ld, ld> LDP;
typedef pair<ll, ll> LP;
#define fr first
#define sc second
#define all(c) c.begin(), c.end()
#define pb push_back
#define debug(x) cerr << #x << " = " << (x) << endl;
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}

int h, w, m;

void solve() {
  cin >> h >> w >> m;
  vector<int> cnth(h, 0), cntw(w, 0);
  map<P, bool> mp;
  rep(i, m) {
    int x, y;
    cin >> x >> y;
    --x, --y;
    mp[P{x, y}] = 1;
    cnth[x]++, cntw[y]++;
  }
  set<int> sex, sey;
  int mah = -1;
  rep(i, h) {
    if (chmax(mah, cnth[i])) {
      sex.clear();
      sex.insert(i);
    } else if (mah == cnth[i]) {
      sex.insert(i);
    }
  }
  int maw = -1;
  rep(i, w) {
    if (chmax(maw, cntw[i])) {
      sey.clear();
      sey.insert(i);
    } else if (maw == cntw[i]) {
      sey.insert(i);
    }
  }
  int ans = mah + maw;
  bool check = 1;
  for (auto x : sex) {
    for (auto y : sey) {
      if (!mp[P{x, y}]) {
        check = 0;
      }
    }
  }
  if (check)
    --ans;
  cout << ans << endl;
}

signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  // cout << fixed << setprecision(10);
  // int t; cin >> t; rep(i, t)solve();
  solve();
  return 0;
}

Fixed submission:
/**
 *    author:  otera
 **/
#include <algorithm>
#include <bitset>
#include <cassert>
#include <ciso646>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstring>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;

// #define int long long
typedef long long ll;
typedef unsigned long long ul;
typedef unsigned int ui;
typedef long double ld;
const int inf = 1e9 + 7;
const ll INF = 1LL << 60;
const ll mod = 1e9 + 7;
#define rep(i, n) for (int i = 0; i < n; i++)
#define per(i, n) for (int i = n - 1; i >= 0; i--)
#define Rep(i, sta, n) for (int i = sta; i < n; i++)
#define rep1(i, n) for (int i = 1; i <= n; i++)
#define per1(i, n) for (int i = n; i >= 1; i--)
#define Rep1(i, sta, n) for (int i = sta; i <= n; i++)
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<int, int> P;
typedef pair<ld, ld> LDP;
typedef pair<ll, ll> LP;
#define fr first
#define sc second
#define all(c) c.begin(), c.end()
#define pb push_back
#define debug(x) cerr << #x << " = " << (x) << endl;
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}

int h, w, m;

void solve() {
  cin >> h >> w >> m;
  vector<int> cnth(h, 0), cntw(w, 0);
  map<P, bool> mp;
  rep(i, m) {
    int x, y;
    cin >> x >> y;
    --x, --y;
    mp[P{x, y}] = 1;
    cnth[x]++, cntw[y]++;
  }
  set<int> sex, sey;
  int mah = -1;
  rep(i, h) {
    if (chmax(mah, cnth[i])) {
      sex.clear();
      sex.insert(i);
    } else if (mah == cnth[i]) {
      sex.insert(i);
    }
  }
  int maw = -1;
  rep(i, w) {
    if (chmax(maw, cntw[i])) {
      sey.clear();
      sey.insert(i);
    } else if (maw == cntw[i]) {
      sey.insert(i);
    }
  }
  int ans = mah + maw;
  bool check = 1;
  for (auto x : sex) {
    for (auto y : sey) {
      if (!mp[P{x, y}]) {
        check = 0;
        break;
      }
    }
  }
  if (check)
    --ans;
  cout << ans << endl;
}

signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  // cout << fixed << setprecision(10);
  // int t; cin >> t; rep(i, t)solve();
  solve();
  return 0;
}