Language: C++

#include<iostream>
#include<algorithm>
#include<vector>
#define LL long long 
int N;
int time[13];
bool used[48];
int ans;
std::vector<int> t;
void dfs(int n) {
	if (n == t.size()) {
		int res = 100;
		std::vector<int> copy = t;
		std::sort(copy.begin(), copy.end());
		for (int i = 1; i < copy.size(); i++) {
			res = std::min(res, copy[i] - copy[i - 1]);
		}
		res = std::min(res, copy[0] + 24 - copy[copy.size()-1]);
		ans = std::max(res, ans);
		return;
	}
	dfs(n + 1);
	t[n] = 24 - t[n];
	dfs(n + 1);
	t[n] = 24 - t[n];
	return;
}
int main() {
	time[0]++;
	std::cin >> N;
	if (N == 1) {
		int tmp;
		std::cin >> tmp;
		std::cout << tmp << std::endl;
		return 0;
	}
	for (int i = 1; i <= N; i++) {
		int tmp;
		std::cin >> tmp;
		time[tmp]++;
	}
	if (time[0] > 1 || time[12] > 1) {
		std::cout << 0 << std::endl;
		return 0;
	}
	for (int i = 0; i <= 12; i++) {
		if (time[i] >= 1)t.emplace_back(i);
		if (time[i] >= 2)t.emplace_back(i);
		if (time[i] >= 3) {
			std::cout << 0 << std::endl;
			return 0;
		}
	}
	dfs(1);
	std::cout << ans << std::endl;
	return 0;
}

Compiler output:
a.cc:6:12: error: 'int time [13]' redeclared as different kind of entity
    6 | int time[13];
      |            ^
In file included from /usr/include/pthread.h:23,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/gthr-default.h:35,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/gthr.h:157,
                 from /usr/include/c++/14/ext/atomicity.h:35,
                 from /usr/include/c++/14/bits/ios_base.h:39,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:1:
/usr/include/time.h:76:15: note: previous declaration 'time_t time(time_t*)'
   76 | extern time_t time (time_t *__timer) __THROW;
      |               ^~~~
a.cc: In function 'int main()':
a.cc:29:15: warning: pointer to a function used in arithmetic [-Wpointer-arith]
   29 |         time[0]++;
      |               ^
a.cc:29:15: warning: ISO C++ forbids incrementing a pointer of type 'time_t (*)(time_t*) noexcept' {aka 'long int (*)(long int*) noexcept'} [-Wpointer-arith]
   29 |         time[0]++;
      |         ~~~~~~^
a.cc:29:15: error: lvalue required as increment operand
   29 |         time[0]++;
      |               ^
a.cc:40:25: warning: pointer to a function used in arithmetic [-Wpointer-arith]
   40 |                 time[tmp]++;
      |                         ^
a.cc:40:25: warning: ISO C++ forbids incrementing a pointer of type 'time_t (*)(time_t*) noexcept' {aka 'long int (*)(long int*) noexcept'} [-Wpointer-arith]
   40 |                 time[tmp]++;
      |                 ~~~~~~~~^
a.cc:40:25: error: lvalue required as increment operand
   40 |                 time[tmp]++;
      |                         ^
a.cc:42:19: warning: pointer to a function used in arithmetic [-Wpointer-arith]
   42 |         if (time[0] > 1 || time[12] > 1) {
      |                   ^
a.cc:42:21: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   42 |         if (time[0] > 1 || time[12] > 1) {
      |             ~~~~~~~~^~~
a.cc:42:35: warning: pointer to a function used in arithmetic [-Wpointer-arith]
   42 |         if (time[0] > 1 || time[12] > 1) {
      |                                   ^
a.cc:42:37: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   42 |         if (time[0] > 1 || time[12] > 1) {
      |                            ~~~~~~~~~^~~
a.cc:47:27: warning: pointer to a function used in arithmetic [-Wpointer-arith]
   47 |                 if (time[i] >= 1)t.emplace_back(i);
      |                           ^
a.cc:47:29: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   47 |                 if (time[i] >= 1)t.emplace_back(i);
      |                     ~~~~~~~~^~~~
a.cc:48:27: warning: pointer to a function used in arithmetic [-Wpointer-arith]
   48 |                 if (time[i] >= 2)t.emplace_back(i);
      |                           ^
a.cc:48:29: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   48 |                 if (time[i] >= 2)t.emplace_back(i);
      |                     ~~~~~~~~^~~~
a.cc:49:27: warning: pointer to a function used in arithmetic [-Wpointer-arith]
   49 |                 if (time[i] >= 3) {
      |                           ^
a.cc:49:29: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   49 |                 if (time[i] >= 3) {
      |                     ~~~~~~~~^~~~