Language: C++

#include <iostream>
#include <map>
using namespace std;
int main()
{
 int N,M;
 cin >>N >> M;
 map<long,long>A;
 int  a;
 int  b;

 for(int i=0;i<N;i++){
cin >> a >> b;
 A.insert(make_pair(a,b));
}
long sumMoney=0;
  for(auto i=A.begin();i<=A.end();++i){
  if(M>i->second){
  sumMoney+=i->first*i->second;
  M-=i->second;
  }
  else
  {
    sumMoney+=i->first*M;  
    M=0;
  }
  if(M==0)
  break;
  }

  cout << sumMoney << endl;
return 0;

}

Compiler output:
a.cc: In function 'int main()':
a.cc:17:25: error: no match for 'operator<=' (operand types are 'std::_Rb_tree_iterator<std::pair<const long int, long int> >' and 'std::map<long int, long int>::iterator' {aka 'std::_Rb_tree<long int, std::pair<const long int, long int>, std::_Select1st<std::pair<const long int, long int> >, std::less<long int>, std::allocator<std::pair<const long int, long int> > >::iterator'})
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                        ~^~~~~~~~~
      |                        |       |
      |                        |       _Rb_tree_iterator<[...]>
      |                        _Rb_tree_iterator<[...]>
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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'const std::reverse_iterator<_Iterator>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
/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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'const std::reverse_iterator<_Iterator>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
/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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'const std::move_iterator<_IteratorL>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
/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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'const std::move_iterator<_IteratorL>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'const std::pair<_T1, _T2>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
/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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
/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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
/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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
/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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
/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:17:33: note:   mismatched types 'const _CharT*' and 'std::_Rb_tree_iterator<std::pair<const long int, long int> >'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
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:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'const std::tuple<_UTypes ...>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
In file included from /usr/include/c++/14/map:63,
                 from a.cc:2:
/usr/include/c++/14/bits/stl_map.h:1571:5: note: candidate: 'template<class _Key, class _Tp, class _Compare, class _Alloc> bool std::operator<=(const map<_Key, _Tp, _Compare, _Allocator>&, const map<_Key, _Tp, _Compare, _Allocator>&)'
 1571 |     operator<=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:1571:5: note:   template argument deduction/substitution failed:
a.cc:17:33: note:   'std::_Rb_tree_iterator<std::pair<const long int, long int> >' is not derived from 'const std::map<_Key, _Tp, _Compare, _Allocator>'
   17 |   for(auto i=A.begin();i<=A.end();++i){
      |                                 ^
In file included from /usr/include/c++/14/map:64:
/usr/include/c++/14/bits/stl_multimap.h:1193:5: note: candidate: 'template<class _Key, class _Tp, class _Compare, class _Alloc> bool std::operator<=(const multimap<_Key, _Tp, _Compare, _Allocator>&, const multimap<_Key, _Tp, _Compare, _Allocator>&)'
 1193 |     operator<=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_multimap.h:1193:5: note:   template argument deduction/substitution failed:
a.cc:17:33: note:   'std::_Rb_tree_iterato