Language: C++

#include <iostream>
#include <vector>
#include <algorithm>
#include <cstdlib>

using namespace std;

bool Inside(int n,int k,int i,int j,vector<long long> x,vector<long long> y,bool flag) {
    int count = 0;
    if(flag){
        for(int a = 0;a < n;a++) {
            if(x[a] >= x[i] && x[a] <= x[j] && y[a] >= y[i] && y[a] <= y[j]){
                count++;
            }
        }
    }else{
        for(int a = 0;a < n;a++) {
            if(x[a] <= x[i] && x[a] >= x[j] && y[a] >= y[i] && y[a] <= y[j]){
                count++;
            }
        }
    }
    if (count == k) return true;
    else return false;
    
}

int main() {
    int n,k;
    vector<long long> x,y;
    long long sub;
    bool flag;
    long long min = 9223372036854775807;
    long long S;

    cin >> n >> k;

    for(int i = 0;i < n;i++) {
        cin >> sub;
        x.push_back(sub);
        cin >> sub;
        y.push_back(sub);
    }

    for(int i = 0;i < n;i++) {
        for(int j = 0;j < n;j++) {
            if(x[i] <= [j]) flag = true;
            else flag = false;
            if(y[i] > y[j]) swap(i,j);
            if(Inside(n,k,i,j,x,y,flag)){
                S = abs(x[i] - x[j]) * abs(y[i] - y[j]);
                if(S < min) min = S;
            }
            
        }
    }

    cout << min << endl;

    return 0;

}

Compiler output:
a.cc: In lambda function:
a.cc:47:27: error: expected '{' before ')' token
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
a.cc: In function 'int main()':
a.cc:47:21: error: no match for 'operator<=' (operand types are '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'} and 'main()::<lambda()>')
   47 |             if(x[i] <= [j]) flag = true;
In file included from /usr/include/c++/14/string:48,
                 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:1:
/usr/include/c++/14/bits/stl_iterator.h:469:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<=(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  469 |     operator<=(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:469:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'}
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
/usr/include/c++/14/bits/stl_iterator.h:513:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<=(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  513 |     operator<=(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:513:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'}
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
/usr/include/c++/14/bits/stl_iterator.h:1704:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<=(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1704 |     operator<=(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1704:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const std::move_iterator<_IteratorL>' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'}
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
/usr/include/c++/14/bits/stl_iterator.h:1767:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<=(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1767 |     operator<=(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1767:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const std::move_iterator<_IteratorL>' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'}
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/string:51:
/usr/include/c++/14/bits/stl_pair.h:1064:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator<=(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1064 |     operator<=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1064:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const std::pair<_T1, _T2>' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'}
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
In file included from /usr/include/c++/14/bits/basic_string.h:47,
                 from /usr/include/c++/14/string:54:
/usr/include/c++/14/string_view:717:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<=(basic_string_view<_CharT, _Traits>, basic_string_view<_CharT, _Traits>)'
  717 |     operator<=(basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:717:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'std::basic_string_view<_CharT, _Traits>' and 'long long int'
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
/usr/include/c++/14/string_view:724:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<=(basic_string_view<_CharT, _Traits>, __type_identity_t<basic_string_view<_CharT, _Traits> >)'
  724 |     operator<=(basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:724:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'std::basic_string_view<_CharT, _Traits>' and 'long long int'
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
/usr/include/c++/14/string_view:732:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator<=(__type_identity_t<basic_string_view<_CharT, _Traits> >, basic_string_view<_CharT, _Traits>)'
  732 |     operator<=(__type_identity_t<basic_string_view<_CharT, _Traits>> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:732:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   'main()::<lambda()>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
/usr/include/c++/14/bits/basic_string.h:3956:5: 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>&)'
 3956 |     operator<=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3956:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'}
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
/usr/include/c++/14/bits/basic_string.h:3970:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator<=(const __cxx11::basic_string<_CharT, _Traits, _Allocator>&, const _CharT*)'
 3970 |     operator<=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3970:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'}
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
/usr/include/c++/14/bits/basic_string.h:3983:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator<=(const _CharT*, const __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 3983 |     operator<=(const _CharT* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:3983:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const _CharT*' and 'long long int'
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
In file included from /usr/include/c++/14/bits/memory_resource.h:47,
                 from /usr/include/c++/14/string:68:
/usr/include/c++/14/tuple:2625:5: note: candidate: 'template<class ... _TElements, class ... _UElements> constexpr bool std::operator<=(const tuple<_UTypes ...>&, const tuple<_Elements ...>&)'
 2625 |     operator<=(const tuple<_TElements...>& __t,
      |     ^~~~~~~~
/usr/include/c++/14/tuple:2625:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const std::tuple<_UTypes ...>' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'}
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^
In file included from /usr/include/c++/14/vector:66,
                 from a.cc:2:
/usr/include/c++/14/bits/stl_vector.h:2108:5: note: candidate: 'template<class _Tp, class _Alloc> bool std::operator<=(const vector<_Tp, _Alloc>&, const vector<_Tp, _Alloc>&)'
 2108 |     operator<=(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_vector.h:2108:5: note:   template argument deduction/substitution failed:
a.cc:47:27: note:   mismatched types 'const std::vector<_Tp, _Alloc>' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'}
   47 |             if(x[i] <= [j]) flag = true;
      |                           ^