Language: C++

#include <stdio.h>
#include <cstdio>
#include <vector>
#include <iostream>
#include <string.h>
#include <cstring>
#include <algorithm>
#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(int i = m;i < n;i++)
#define FORR(i, m, n) for(int i = m;i >= n;i--)
#define SORT(v, n) sort(v, v+n);
#define VSORT(v) sort(v.begin(), v.end());
#define llong long long
#define pb(a) push_back(a)
#define INF 999999999
using namespace std;

int dy[]={0, 0, 1, -1, 0};
int dx[]={1, -1, 0, 0, 0};

int main(){
	int n, m, x;
	int cnt_0 = 0, cnt_n = 0;
	vector<int> a(m);
	REP(i, a){
		cin >> a[i];
		if(0 < a[i] && a[i] < x){
			cnt_0 += 1;
		}else if(x < a[i] && a[i] < n){
			cnt_n += 1;
		}
		if (cnt_0 < cnt_n){
			cout << cnt_0 << "\n";
		}else {
			cout << cnt_n << "\n";
		}
	}

}


Compiler output:
a.cc: In function 'int main()':
a.cc:8:35: error: no match for 'operator<' (operand types are 'int' and 'std::vector<int>')
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                   ^
a.cc:26:9: note: in expansion of macro 'REP'
   26 |         REP(i, a){
      |         ^~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/vector:62,
                 from a.cc:3:
/usr/include/c++/14/bits/stl_pair.h:1045:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator<(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1045 |     operator<(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1045:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const std::pair<_T1, _T2>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:67:
/usr/include/c++/14/bits/stl_iterator.h:448:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  448 |     operator<(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:448:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
/usr/include/c++/14/bits/stl_iterator.h:493:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  493 |     operator<(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:493:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
/usr/include/c++/14/bits/stl_iterator.h:1694:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1694 |     operator<(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1694:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const std::move_iterator<_IteratorL>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
/usr/include/c++/14/bits/stl_iterator.h:1760:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1760 |     operator<(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1760:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const std::move_iterator<_IteratorL>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
In file included from /usr/include/c++/14/vector:66:
/usr/include/c++/14/bits/stl_vector.h:2089:5: note: candidate: 'template<class _Tp, class _Alloc> bool std::operator<(const vector<_Tp, _Alloc>&, const vector<_Tp, _Alloc>&)'
 2089 |     operator<(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_vector.h:2089:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const std::vector<_Tp, _Alloc>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
In file included from /usr/include/c++/14/bits/memory_resource.h:47,
                 from /usr/include/c++/14/vector:87:
/usr/include/c++/14/tuple:2600:5: note: candidate: 'template<class ... _TElements, class ... _UElements> constexpr bool std::operator<(const tuple<_UTypes ...>&, const tuple<_Elements ...>&)'
 2600 |     operator<(const tuple<_TElements...>& __t,
      |     ^~~~~~~~
/usr/include/c++/14/tuple:2600:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const std::tuple<_UTypes ...>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
In file included from /usr/include/c++/14/bits/basic_string.h:47,
                 from /usr/include/c++/14/string:54,
                 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:4:
/usr/include/c++/14/string_view:673:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<(basic_string_view<_CharT, _Traits>, basic_string_view<_CharT, _Traits>)'
  673 |     operator< (basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:673:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'std::basic_string_view<_CharT, _Traits>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
/usr/include/c++/14/string_view:680:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<(basic_string_view<_CharT, _Traits>, __type_identity_t<basic_string_view<_CharT, _Traits> >)'
  680 |     operator< (basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:680:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'std::basic_string_view<_CharT, _Traits>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
/usr/include/c++/14/string_view:688:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<(__type_identity_t<basic_string_view<_CharT, _Traits> >, basic_string_view<_CharT, _Traits>)'
  688 |     operator< (__type_identity_t<basic_string_view<_CharT, _Traits>> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:688:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   'std::vector<int>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
/usr/include/c++/14/bits/basic_string.h:3874:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator<(const __cxx11::basic_string<_CharT, _Traits, _Allocator>&, const __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 3874 |     operator<(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3874:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
/usr/include/c++/14/bits/basic_string.h:3888:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator<(const __cxx11::basic_string<_CharT, _Traits, _Allocator>&, const _CharT*)'
 3888 |     operator<(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3888:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
/usr/include/c++/14/bits/basic_string.h:3901:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator<(const _CharT*, const __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 3901 |     operator<(const _CharT* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3901:5: note:   template argument deduction/substitution failed:
a.cc:26:16: note:   mismatched types 'const _CharT*' and 'int'
   26 |         REP(i, a){
      |                ^
a.cc:8:37: note: in definition of macro 'REP'
    8 | #define REP(i, n) for(int i = 0;i < n;i++)
      |                                     ^
In file included from /usr/include/c++/14/bits/ios_base.h:46:
/usr/include/c++/14/system_error:324:3: note: candidate: 'bool std::operator<(const error_code&, const error_code&)'
  324 |   operator<(const error_code& __lhs, const error_code& __rhs) noexcept
      |   ^~~~~~~~
/usr/include/c++/14/system_error