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

#include <algorithm>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <cstdint>
#include <cstring>
#include <deque>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;
#define loop(n, i, a) for (ll i = a; i < n; i++)
#define loopR(n, i, a) for (ll i = a - 1; i >= n; i--)
#define all(arr, n) arr, arr + n
#define allv(v) (v).begin(), (v).end()
#define rallv(v) (v).rbegin(), (v).rend()
#define m_p make_pair
#define ll long long
#define pii pair<ll, ll>
#define vi vector<int>
#define vll vector<ll>
#define vii vector<pii>
#define sz(x) (int)x.size()
#define pb push_back
#define endl "\\n"
#define Endl "\\n"
#define f first
#define s second
#define mem(dp, n) memset(dp, n, sizeof dp)
int dx[] = {1, 0, -1, 0, -1, -1, 1, 1};
int dy[] = {0, 1, 0, -1, -1, 1, -1, 1};
int KnightI[] = {2, 1, -1, -2, -2, -1, 1, 2};
int KnightJ[] = {1, 2, 2, 1, -1, -2, -2, -1};
template <typename T> void max_self(T &a, T b) { a = max(a, b); }
template <typename T> void min_self(T &a, T b) { a = min(a, b); }
void fast() {
  std::ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cout.tie(NULL);
}
vector<string> vec_splitter(string s) {
  s += ',';
  vector<string> res;
  while (!s.empty()) {
    res.push_back(s.substr(0, s.find(',')));
    s = s.substr(s.find(',') + 1);
  }
  return res;
}
void debug_out(vector<string> __attribute__((unused)) args,
               __attribute__((unused)) int idx,
               __attribute__((unused)) int LINE_NUM) {
  cerr << endl;
}
template <typename Head, typename... Tail>
void debug_out(vector<string> args, int idx, int LINE_NUM, Head H, Tail... T) {
  if (idx > 0)
    cerr << ", ";
  else
    cerr << "Line(" << LINE_NUM << ") ";
  stringstream ss;
  ss << H;
  cerr << args[idx] << " = " << ss.str();
  debug_out(args, idx + 1, LINE_NUM, T...);
}
#define debug(...)                                                             \\
  debug_out(vec_splitter(#__VA_ARGS__), 0, __LINE__, __VA_ARGS__)
const ll mxN = 5e5 + 10, oo = 0x3f3f3f3f, MOD = 1e9 + 7;
const long double PI = acos(-1), eps = 1.0e-14;

void solve() {
  int h, w, m;
  cin >> h >> w >> m;
  map<ll, ll> row, col;
  map<pii, ll> cells;
  loop(m, i, 0) {
    int x, y;
    cin >> x >> y;
    row[x]++;
    col[y]++;
    cells[{x, y}]++;
  }
  ll mxr = 0, mxc = 0;
  vll r, c;
  loop(h + 1, i, 0) max_self(mxr, row[i]);
  loop(w + 1, i, 0) max_self(mxc, col[i]);
  loop(h + 1, i, 0) if (mxr == row[i]) r.pb(i);
  loop(w + 1, i, 0) if (mxc == col[i]) c.pb(i);
  int res = mxr + mxc;
  bool flag = true;
  for (auto x : r) {
    for (auto y : c) {
      if (!cells[{x, y}]) {
        flag = false;
        break;
      }
    }
  }
  cout << res - flag << Endl;
}
int main() {
#ifndef ONLINE_JUDGE
  freopen("input.txt", "r", stdin);
  freopen("output.txt", "w", stdout);
#endif
  fast();
  solve();
}


Error: TLE

Fixed submission:

#include <algorithm>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <cstdint>
#include <cstring>
#include <deque>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;
#define loop(n, i, a) for (ll i = a; i < n; i++)
#define loopR(n, i, a) for (ll i = a - 1; i >= n; i--)
#define all(arr, n) arr, arr + n
#define allv(v) (v).begin(), (v).end()
#define rallv(v) (v).rbegin(), (v).rend()
#define m_p make_pair
#define ll long long
#define pii pair<ll, ll>
#define vi vector<int>
#define vll vector<ll>
#define vii vector<pii>
#define sz(x) (int)x.size()
#define pb push_back
#define endl "\\n"
#define Endl "\\n"
#define f first
#define s second
#define mem(dp, n) memset(dp, n, sizeof dp)
int dx[] = {1, 0, -1, 0, -1, -1, 1, 1};
int dy[] = {0, 1, 0, -1, -1, 1, -1, 1};
int KnightI[] = {2, 1, -1, -2, -2, -1, 1, 2};
int KnightJ[] = {1, 2, 2, 1, -1, -2, -2, -1};
template <typename T> void max_self(T &a, T b) { a = max(a, b); }
template <typename T> void min_self(T &a, T b) { a = min(a, b); }
void fast() {
  std::ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cout.tie(NULL);
}
vector<string> vec_splitter(string s) {
  s += ',';
  vector<string> res;
  while (!s.empty()) {
    res.push_back(s.substr(0, s.find(',')));
    s = s.substr(s.find(',') + 1);
  }
  return res;
}
void debug_out(vector<string> __attribute__((unused)) args,
               __attribute__((unused)) int idx,
               __attribute__((unused)) int LINE_NUM) {
  cerr << endl;
}
template <typename Head, typename... Tail>
void debug_out(vector<string> args, int idx, int LINE_NUM, Head H, Tail... T) {
  if (idx > 0)
    cerr << ", ";
  else
    cerr << "Line(" << LINE_NUM << ") ";
  stringstream ss;
  ss << H;
  cerr << args[idx] << " = " << ss.str();
  debug_out(args, idx + 1, LINE_NUM, T...);
}
#define debug(...)                                                             \\
  debug_out(vec_splitter(#__VA_ARGS__), 0, __LINE__, __VA_ARGS__)
const ll mxN = 5e5 + 10, oo = 0x3f3f3f3f, MOD = 1e9 + 7;
const long double PI = acos(-1), eps = 1.0e-14;

void solve() {
  int h, w, m;
  cin >> h >> w >> m;
  map<ll, ll> row, col;
  map<pii, ll> cells;
  loop(m, i, 0) {
    int x, y;
    cin >> x >> y;
    row[x]++;
    col[y]++;
    cells[{x, y}]++;
  }
  ll mxr = 0, mxc = 0;
  vll r, c;
  loop(h + 1, i, 0) max_self(mxr, row[i]);
  loop(w + 1, i, 0) max_self(mxc, col[i]);
  loop(h + 1, i, 0) if (mxr == row[i]) r.pb(i);
  loop(w + 1, i, 0) if (mxc == col[i]) c.pb(i);
  int res = mxr + mxc;
  bool flag = true;
  for (auto x : r) {
    for (auto y : c) {
      if (!cells[{x, y}])
        flag = false;
    }
  }
  cout << res - flag << Endl;
}
int main() {
#ifndef ONLINE_JUDGE
  freopen("input.txt", "r", stdin);
  freopen("output.txt", "w", stdout);
#endif
  fast();
  solve();
}