Language: C++

#include"bits/stdc++.h"
using namespace std;
namespace ORIGIN {
	#define LL long long
	#define VLL vector<long long>
	#define SORT(x) sort(x.begin(),x.end())
	#define REVE(x) reverse(x.begin(),x.end())
	#define rep(i,n) for(int i=0;i<n;i++)
	#define COUT(x) cout<<x<<endl
	double pai = 3.1415926535;
	string atc = "atcoder";
	typedef pair<long long, long long> data_t;
	string strnum = "0123456789";
	string alpS = "abcdefghijklmnopqrstuvwxyz";
	string alpL = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	int sizealp = (int)(alpS.size());
	int mod = 1e9 + 7;
	bool test = false;
}
using namespace ORIGIN;

void Test(char a) {
	if (test) {
		printf("%c", a);
	}
}
int gcd(LL a, LL b) {
	if (a == 0 || b == 0)return 0;
	if (a < b)swap(a, b);
	if (a % b == 0)return b;
	else gcd(b, a % b);
}

int main() {
	int N;
	cin >> N;
	VLL A(N);
	rep(i, N)cin >> A[i];
	VLL L, R;
	L.push_back(A[0]);
	for (int i = 1; i < N; i++) {
		L.push_back(gcd(A[i], L[i - 1]));
	}
	REVE(A);
	R.push_back(A[0]);
	for (int i = 1; i < N; i++) {
		R.push_back(gcd(A[i], R[i - 1]));
	}
	REVE(A);
	REVE(R);
	int MAX=0;
	for (int i = 0; i < N; i++) {
		if (i == 0) {
			MAX = R[i+1];
		}
		else if (i == N - 1) {
			MAX = max(L[i - 1], MAX);
		}
		else {
			MAX = max(gcd(L[i - 1], R[i + 1]), MAX);
		}
	}
	COUT(MAX);
}


Compiler output:
a.cc: In function 'int main()':
a.cc:57:34: error: no matching function for call to 'max(__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type&, int&)'
   57 |                         MAX = max(L[i - 1], MAX);
      |                               ~~~^~~~~~~~~~~~~~~
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:1:
/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:   template argument deduction/substitution failed:
a.cc:57:34: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   57 |                         MAX = max(L[i - 1], MAX);
      |                               ~~~^~~~~~~~~~~~~~~
/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, 2 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:   candidate expects 1 argument, 2 provided
/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:   template argument deduction/substitution failed:
a.cc:57:34: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   57 |                         MAX = max(L[i - 1], MAX);
      |                               ~~~^~~~~~~~~~~~~~~
a.cc: In function 'int gcd(long long int, long long int)':
a.cc:31:17: warning: control reaches end of non-void function [-Wreturn-type]
   31 |         else gcd(b, a % b);
      |              ~~~^~~~~~~~~~