Problem p02580 (C++)

Buggy submission (status: Time Limit Exceeded):
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long int
using namespace __gnu_pbds;
typedef tree<pair<ll, pair<ll, ll>>, null_type, less<pair<ll, pair<ll, ll>>>,
             rb_tree_tag, tree_order_statistics_node_update>
    ordered_set;
#define me BOSS
#define bug() cout << "AIkahne aise" << endl
#define PI acos(-1)
/* Precode Start Here *\
     Sieve
void sieve()
{
    for(ll i=3; i<=2000; i+=2)
    {
        for(ll j=i*i; j<=4000000; j+=i)
            A[j]=1;
    }
    v.push_back(2);
    for(ll i=3; i<=4000000; i+=2)
        if(A[i]==0)
            v.push_back(i);
}

     Power Function Modulo P

ll modPow(ll a, ll x, ll p) {
    //calculates a^x mod p in logarithmic time.
    long res = 1;
    while(x > 0) {
        if( x % 2 != 0) {
            res = (res * a) % p;
        }
        a = (a * a) % p;
        x /= 2;
    }
    return res;
}


   factorial

ll fact(ll n)
{
    ll ans=1;
    for(ll i=1;i<=n;i++)
    {
        ans=(ans*i)%mod;
    }
    return ans;
}
     Calculating nCr using Fermats law Theorem

ll modInverse(ll a, ll p) {
    //calculates the modular multiplicative of a mod m.
    //(assuming p is prime).
    return modPow(a, p-2, p);
}


ll modBinomial(ll n, ll k, ll p) {
// calculates C(n,k) mod p (assuming p is prime).

    ll numerator = 1; // n * (n-1) * ... * (n-k+1)
    for (ll i=0; i<k; i++) {
        numerator = (numerator * (n-i) ) % p;
    }

    ll denominator = 1; // k!
    for (ll i=1; i<=k; i++) {
        denominator = (denominator * i) % p;
    }

    // numerator / denominator mod p.
    return ( numerator* modInverse(denominator,p) ) % p;
}
     num of divisor and euler totient

ll phi[1000001],mark[1000001],divi[1000001];;
void divisorPhi(ll n)
{
    for(int i=1;i<=n;i++)
        phi[i]=i;
    for(int i=2;i<=n;i++)
    {
        if(!mark[i])
        {
            for(int j=i;j<=n;j+=i)
            {
                mark[j]=1;
                phi[j]*=(1-1/(double)i);
            }
        }
    }
    for(ll i=1;i<=n;i++)
    {
        for(ll j=i;j<=n;j+=i)
            divi[j]++;
    }
}
/* Precode Ends */
#define mod 1000000007
ll A[5000001], B[5000001];
vector<ll> hia;
vector<ll> nah;
ll rowMap[300001], colMap[300001];
map<pair<ll, ll>, ll> myMap;
set<ll> mySet;
vector<pair<ll, ll>> vp;
priority_queue<ll> pq;
priority_queue<ll, vector<ll>, std::greater<ll>> first;
ll po(ll a, ll n) {
  ll ans = 1;
  for (int i = 1; i <= n; i++)
    ans *= a;
  return ans;
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  ll r, c, m, a, b, row = 0, col = 0;
  cin >> r >> c >> m;
  for (int i = 1; i <= m; i++) {
    cin >> a >> b;
    rowMap[a]++;
    colMap[b]++;
    myMap[make_pair(a, b)] = 1;
  }
  for (int i = 1; i <= r; i++) {
    row = max(row, rowMap[i]);
  }
  for (int i = 1; i <= r; i++) {
    if (row == rowMap[i]) {
      hia.push_back(i);
    }
  }
  for (int i = 1; i <= c; i++) {
    col = max(col, colMap[i]);
  }
  for (int i = 1; i <= c; i++) {
    if (col == colMap[i]) {
      nah.push_back(i);
    }
  }
  ll f = 0;
  for (int i = 0; i < hia.size(); i++) {
    for (int j = 0; j < nah.size(); j++) {
      if (myMap[make_pair(hia[i], nah[j])] == 0) {
        f = 1;
      }
    }
  }
  if (f == 1) {
    cout << row + col << endl;
  } else
    cout << row + col - 1 << endl;
  return 0;
}


Fixed submission:
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long int
using namespace __gnu_pbds;
typedef tree<pair<ll, pair<ll, ll>>, null_type, less<pair<ll, pair<ll, ll>>>,
             rb_tree_tag, tree_order_statistics_node_update>
    ordered_set;
#define me BOSS
#define bug() cout << "AIkahne aise" << endl
#define PI acos(-1)
/* Precode Start Here *\
     Sieve
void sieve()
{
    for(ll i=3; i<=2000; i+=2)
    {
        for(ll j=i*i; j<=4000000; j+=i)
            A[j]=1;
    }
    v.push_back(2);
    for(ll i=3; i<=4000000; i+=2)
        if(A[i]==0)
            v.push_back(i);
}

     Power Function Modulo P

ll modPow(ll a, ll x, ll p) {
    //calculates a^x mod p in logarithmic time.
    long res = 1;
    while(x > 0) {
        if( x % 2 != 0) {
            res = (res * a) % p;
        }
        a = (a * a) % p;
        x /= 2;
    }
    return res;
}


   factorial

ll fact(ll n)
{
    ll ans=1;
    for(ll i=1;i<=n;i++)
    {
        ans=(ans*i)%mod;
    }
    return ans;
}
     Calculating nCr using Fermats law Theorem

ll modInverse(ll a, ll p) {
    //calculates the modular multiplicative of a mod m.
    //(assuming p is prime).
    return modPow(a, p-2, p);
}


ll modBinomial(ll n, ll k, ll p) {
// calculates C(n,k) mod p (assuming p is prime).

    ll numerator = 1; // n * (n-1) * ... * (n-k+1)
    for (ll i=0; i<k; i++) {
        numerator = (numerator * (n-i) ) % p;
    }

    ll denominator = 1; // k!
    for (ll i=1; i<=k; i++) {
        denominator = (denominator * i) % p;
    }

    // numerator / denominator mod p.
    return ( numerator* modInverse(denominator,p) ) % p;
}
     num of divisor and euler totient

ll phi[1000001],mark[1000001],divi[1000001];;
void divisorPhi(ll n)
{
    for(int i=1;i<=n;i++)
        phi[i]=i;
    for(int i=2;i<=n;i++)
    {
        if(!mark[i])
        {
            for(int j=i;j<=n;j+=i)
            {
                mark[j]=1;
                phi[j]*=(1-1/(double)i);
            }
        }
    }
    for(ll i=1;i<=n;i++)
    {
        for(ll j=i;j<=n;j+=i)
            divi[j]++;
    }
}
/* Precode Ends */
#define mod 1000000007
ll A[5000001], B[5000001];
vector<ll> hia;
vector<ll> nah;
ll rowMap[300001], colMap[300001];
map<pair<ll, ll>, ll> myMap;
set<ll> mySet;
vector<pair<ll, ll>> vp;
priority_queue<ll> pq;
priority_queue<ll, vector<ll>, std::greater<ll>> first;
ll po(ll a, ll n) {
  ll ans = 1;
  for (int i = 1; i <= n; i++)
    ans *= a;
  return ans;
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  ll r, c, m, a, b, row = 0, col = 0;
  cin >> r >> c >> m;
  for (int i = 1; i <= m; i++) {
    cin >> a >> b;
    rowMap[a]++;
    colMap[b]++;
    myMap[make_pair(a, b)] = 1;
  }
  for (int i = 1; i <= r; i++) {
    row = max(row, rowMap[i]);
  }
  for (int i = 1; i <= r; i++) {
    if (row == rowMap[i]) {
      hia.push_back(i);
    }
  }
  for (int i = 1; i <= c; i++) {
    col = max(col, colMap[i]);
  }
  for (int i = 1; i <= c; i++) {
    if (col == colMap[i]) {
      nah.push_back(i);
    }
  }
  ll f = 0;
  for (int i = 0; i < hia.size(); i++) {
    for (int j = 0; j < nah.size(); j++) {
      if (myMap[make_pair(hia[i], nah[j])] == 0) {
        f = 1;
        break;
      }
    }
  }
  if (f == 1) {
    cout << row + col << endl;
  } else
    cout << row + col - 1 << endl;
  return 0;
}