Language: C++

#include<stdio.h>
#include <iostream>
#include<string>
#include<algorithm>
#include<sstream>
#include<math.h>
#include<queue>
#include<stack>
#include<list>
#include<vector>
#include<map>
#include<set>
#define FOR(i,a) for(int i=0;i<a;i++)
#define REP(i,a,b) for(int i=a;i<b;i++)
#define ll long long
using namespace std;

string a;
string b;
bool flg = true;
int main() {
	cin >> a >> b;
	sort(a, aa.size());
	sort(b, b.size());
	FOR(i, a.size()) {
		if (i == b.size()) {
			cout << "No" << endl;
			flg = false;
			break;
		}
		if (a[i] > b[b, size() - i - 1]) {
			cout << "No" << endl;
			flg = false;
			break;
		}
		else if (a[i] < b[b.size() - i - 1) {
			cout << "Yes" << endl;
			flg = false;
			break;
		}
		if (flg)cout << "Yes" << endl;
	}
	return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:23:17: error: 'aa' was not declared in this scope; did you mean 'a'?
   23 |         sort(a, aa.size());
      |                 ^~
      |                 a
a.cc:24:13: error: no matching function for call to 'sort(std::string&, std::__cxx11::basic_string<char>::size_type)'
   24 |         sort(b, b.size());
      |         ~~~~^~~~~~~~~~~~~
In file included from /usr/include/c++/14/algorithm:61,
                 from a.cc:4:
/usr/include/c++/14/bits/stl_algo.h:4762:5: note: candidate: 'template<class _RAIter> void std::sort(_RAIter, _RAIter)'
 4762 |     sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
      |     ^~~~
/usr/include/c++/14/bits/stl_algo.h:4762:5: note:   template argument deduction/substitution failed:
a.cc:24:13: note:   deduced conflicting types for parameter '_RAIter' ('std::__cxx11::basic_string<char>' and 'long unsigned int')
   24 |         sort(b, b.size());
      |         ~~~~^~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algo.h:4793:5: note: candidate: 'template<class _RAIter, class _Compare> void std::sort(_RAIter, _RAIter, _Compare)'
 4793 |     sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
      |     ^~~~
/usr/include/c++/14/bits/stl_algo.h:4793:5: note:   candidate expects 3 arguments, 2 provided
In file included from /usr/include/c++/14/algorithm:86:
/usr/include/c++/14/pstl/glue_algorithm_defs.h:292:1: note: candidate: 'template<class _ExecutionPolicy, class _RandomAccessIterator, class _Compare> __pstl::__internal::__enable_if_execution_policy<_ExecutionPolicy, void> std::sort(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _Compare)'
  292 | sort(_ExecutionPolicy&& __exec, _RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp);
      | ^~~~
/usr/include/c++/14/pstl/glue_algorithm_defs.h:292:1: note:   candidate expects 4 arguments, 2 provided
/usr/include/c++/14/pstl/glue_algorithm_defs.h:296:1: note: candidate: 'template<class _ExecutionPolicy, class _RandomAccessIterator> __pstl::__internal::__enable_if_execution_policy<_ExecutionPolicy, void> std::sort(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator)'
  296 | sort(_ExecutionPolicy&& __exec, _RandomAccessIterator __first, _RandomAccessIterator __last);
      | ^~~~
/usr/include/c++/14/pstl/glue_algorithm_defs.h:296:1: note:   candidate expects 3 arguments, 2 provided
a.cc:31:37: error: no matching function for call to 'size()'
   31 |                 if (a[i] > b[b, size() - i - 1]) {
      |                                 ~~~~^~
In file included from /usr/include/c++/14/string:53,
                 from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:2:
/usr/include/c++/14/bits/range_access.h:262:5: note: candidate: 'template<class _Container> constexpr decltype (__cont.size()) std::size(const _Container&)'
  262 |     size(const _Container& __cont) noexcept(noexcept(__cont.size()))
      |     ^~~~
/usr/include/c++/14/bits/range_access.h:262:5: note:   candidate expects 1 argument, 0 provided
/usr/include/c++/14/bits/range_access.h:272:5: note: candidate: 'template<class _Tp, long unsigned int _Nm> constexpr std::size_t std::size(const _Tp (&)[_Nm])'
  272 |     size(const _Tp (&)[_Nm]) noexcept
      |     ^~~~
/usr/include/c++/14/bits/range_access.h:272:5: note:   candidate expects 1 argument, 0 provided
a.cc:36:51: error: expected ']' before ')' token
   36 |                 else if (a[i] < b[b.size() - i - 1) {
      |                                                   ^
      |                                                   ]