Language: C++

/* 
    @author : srinathbalaji_99
*/


#include<bits/stdc++.h>

#define PB push_back
#define MP make_pair
#define endl '\n'
#define MAX LLONG_MAX
#define MIN LLONG_MIN
#define rep(i, a, b, inc) for(long long i = a; i < b; i += inc)
#define REP(i, n) rep(i, 0, n, 1)
#define MEM(a, b) memset(a, (b), sizeof(a))
#define PI 3.1415926535897932384626433832795
#define MOD 1000000007
#define PLL pair<long long, long long>
#define VL vector<long long>
#define VS vector<string>
#define VLL vector<PLL>
#define VVL vector<VL>
#define MPLL map<long long, long long>
#define UMPLL unordered_map<long long, long long>
#define SETL set<long long>
#define MSETL multiset<long long>
#define GCD(a, b) __gcd(a, b)
#define LCM(a, b) (a * b)/GCD(a, b)
#define ff first
#define ss second
#define pall(a) REP(i, sizeof(a)/sizeof(a[0]))cout << a[i] << " ";cout << endl;
#define pvall(v) REP(i, v.size())cout << v[i] << " ";cout << endl;
#define gall(a, n) REP(i, n)cin >> a[i];
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()

typedef unsigned long long ULL;
typedef long long LL;
typedef long double LD;


using namespace std;

void fast()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
}

int main()
{
    fast();


    LL t,n,i,j,k,x,y,c,m;
    LL a, b;
    cin >> a >> b;
    cout << max(max(a + b, max(a - b, a * b)));
}

Compiler output:
a.cc: In function 'int main()':
a.cc:58:16: error: no matching function for call to 'max(const long long int&)'
   58 |     cout << max(max(a + b, max(a - b, a * b)));
      |             ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51,
                 from a.cc:6:
/usr/include/c++/14/bits/stl_algobase.h:257:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::max(const _Tp&, const _Tp&)'
  257 |     max(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note:   candidate expects 2 arguments, 1 provided
/usr/include/c++/14/bits/stl_algobase.h:303:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare)'
  303 |     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note:   candidate expects 3 arguments, 1 provided
In file included from /usr/include/c++/14/algorithm:61:
/usr/include/c++/14/bits/stl_algo.h:5706:5: note: candidate: 'template<class _Tp> constexpr _Tp std::max(initializer_list<_Tp>)'
 5706 |     max(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5706:5: note:   template argument deduction/substitution failed:
a.cc:58:16: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   58 |     cout << max(max(a + b, max(a - b, a * b)));
      |             ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::max(initializer_list<_Tp>, _Compare)'
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note:   candidate expects 2 arguments, 1 provided