Language: C++

#include <stdio.h>
#include <algorithm>
#include <memory.h>
#include <iostream>
#include <vector>
#include <map>
#include <deque>
  
// Shabdan Batyrkulov
  
using namespace std;
  
#define pb push_back
#define fr first
#define sc second
#define mk make_pair
#define ll long long
#define ld long double
#define vi vector <int>
#define pii pair <int, int>
#define OK puts("OK");                                                                           
                                                                                                
const int N = (int)1e5 + 7;                                                                 
const int inf = (int)1e9 + 7;
const int MAX = (int)1e3+ 7;

int main () {
	unsigned ll a, b; cin >> a >> b;
	unsigned ll mn = 0;
	if (a % 3 == 0 || b % 3 == 0) {
		puts("0");				
	} else {        
		mn = a * b * 2;		
		for (int i = 1; i <= b; i++) {			
			unsigned ll mxx = 0, mnn = inf;
			mxx = max(i * a, max((b - i) * (a / 2), (b - i) * ((a + 1) / 2)));
			mnn = min(i * a, min((b - i) * (a / 2), (b - i) * ((a + 1) / 2)));
			mn = min(mn, abs(mxx - mnn));						 			
		}
		for (int i = 1; i <= a; i++) {			
			unsigned ll mxx = 0, mnn = inf;
			mxx = max(i * b, max((a - i) * (b / 2), (a - i) * ((b + 1) / 2)));
			mnn = min(i * b, min((a - i) * (b / 2), (a - i) * ((b + 1) / 2)));
			mn = min(mn, abs(mxx - mnn));						 			
		}
		cout << mn << endl;	
	}			
} 

Compiler output:
a.cc: In function 'int main()':
a.cc:38:41: error: call of overloaded 'abs(long long unsigned int)' is ambiguous
   38 |                         mn = min(mn, abs(mxx - mnn));
      |                                      ~~~^~~~~~~~~~~
In file included from /usr/include/c++/14/cstdlib:79,
                 from /usr/include/c++/14/bits/stl_algo.h:71,
                 from /usr/include/c++/14/algorithm:61,
                 from a.cc:2:
/usr/include/stdlib.h:980:12: note: candidate: 'int abs(int)'
  980 | extern int abs (int __x) __THROW __attribute__ ((__const__)) __wur;
      |            ^~~
In file included from /usr/include/c++/14/cstdlib:81:
/usr/include/c++/14/bits/std_abs.h:137:3: note: candidate: 'constexpr __float128 std::abs(__float128)'
  137 |   abs(__float128 __x)
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:85:3: note: candidate: 'constexpr __int128 std::abs(__int128)'
   85 |   abs(__GLIBCXX_TYPE_INT_N_0 __x) { return __x >= 0 ? __x : -__x; }
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:79:3: note: candidate: 'constexpr long double std::abs(long double)'
   79 |   abs(long double __x)
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:75:3: note: candidate: 'constexpr float std::abs(float)'
   75 |   abs(float __x)
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:71:3: note: candidate: 'constexpr double std::abs(double)'
   71 |   abs(double __x)
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:61:3: note: candidate: 'long long int std::abs(long long int)'
   61 |   abs(long long __x) { return __builtin_llabs (__x); }
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:56:3: note: candidate: 'long int std::abs(long int)'
   56 |   abs(long __i) { return __builtin_labs(__i); }
      |   ^~~
a.cc:44:41: error: call of overloaded 'abs(long long unsigned int)' is ambiguous
   44 |                         mn = min(mn, abs(mxx - mnn));
      |                                      ~~~^~~~~~~~~~~
/usr/include/stdlib.h:980:12: note: candidate: 'int abs(int)'
  980 | extern int abs (int __x) __THROW __attribute__ ((__const__)) __wur;
      |            ^~~
/usr/include/c++/14/bits/std_abs.h:137:3: note: candidate: 'constexpr __float128 std::abs(__float128)'
  137 |   abs(__float128 __x)
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:85:3: note: candidate: 'constexpr __int128 std::abs(__int128)'
   85 |   abs(__GLIBCXX_TYPE_INT_N_0 __x) { return __x >= 0 ? __x : -__x; }
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:79:3: note: candidate: 'constexpr long double std::abs(long double)'
   79 |   abs(long double __x)
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:75:3: note: candidate: 'constexpr float std::abs(float)'
   75 |   abs(float __x)
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:71:3: note: candidate: 'constexpr double std::abs(double)'
   71 |   abs(double __x)
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:61:3: note: candidate: 'long long int std::abs(long long int)'
   61 |   abs(long long __x) { return __builtin_llabs (__x); }
      |   ^~~
/usr/include/c++/14/bits/std_abs.h:56:3: note: candidate: 'long int std::abs(long int)'
   56 |   abs(long __i) { return __builtin_labs(__i); }
      |   ^~~