Language: C++

#include <bits/stdc++.h>
using namespace std;

int main() {
  int n;
  cin >> n;
  int a[n];
  for(int i=0;i<n;i++){
  	cin >> a[i];
  }
  sort(std::begin(a), std::end(a));
  int sum1=0, sum2=0;
  for(int i=n-1;i>=0;i=i-2){
  	sum1+=a[i];
  }
  for(int i=n-2;i>=0;i=i-2){
  	sum2+=a[i];
  }
  
  cout << sum1-sum2 << endl;

}


Compiler output:
a.cc: In function 'int main()':
a.cc:11:18: error: no matching function for call to 'begin(int [n])'
   11 |   sort(std::begin(a), std::end(a));
      |        ~~~~~~~~~~^~~
In file included from /usr/include/c++/14/bits/algorithmfwd.h:39,
                 from /usr/include/c++/14/bits/stl_algo.h:59,
                 from /usr/include/c++/14/algorithm:61,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51,
                 from a.cc:1:
/usr/include/c++/14/initializer_list:88:5: note: candidate: 'template<class _Tp> constexpr const _Tp* std::begin(initializer_list<_Tp>)'
   88 |     begin(initializer_list<_Tp> __ils) noexcept
      |     ^~~~~
/usr/include/c++/14/initializer_list:88:5: note:   template argument deduction/substitution failed:
a.cc:11:18: note:   mismatched types 'std::initializer_list<_Tp>' and 'int*'
   11 |   sort(std::begin(a), std::end(a));
      |        ~~~~~~~~~~^~~
In file included from /usr/include/c++/14/string:53,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52:
/usr/include/c++/14/bits/range_access.h:52:5: note: candidate: 'template<class _Container> constexpr decltype (__cont.begin()) std::begin(_Container&)'
   52 |     begin(_Container& __cont) -> decltype(__cont.begin())
      |     ^~~~~
/usr/include/c++/14/bits/range_access.h:52:5: note:   template argument deduction/substitution failed:
a.cc:11:18: note:   variable-sized array type 'int [n]' is not a valid template argument
   11 |   sort(std::begin(a), std::end(a));
      |        ~~~~~~~~~~^~~
/usr/include/c++/14/bits/range_access.h:63:5: note: candidate: 'template<class _Container> constexpr decltype (__cont.begin()) std::begin(const _Container&)'
   63 |     begin(const _Container& __cont) -> decltype(__cont.begin())
      |     ^~~~~
/usr/include/c++/14/bits/range_access.h:63:5: note:   template argument deduction/substitution failed:
a.cc:11:18: note:   variable-sized array type 'int [n]' is not a valid template argument
   11 |   sort(std::begin(a), std::end(a));
      |        ~~~~~~~~~~^~~
/usr/include/c++/14/bits/range_access.h:95:5: note: candidate: 'template<class _Tp, long unsigned int _Nm> constexpr _Tp* std::begin(_Tp (&)[_Nm])'
   95 |     begin(_Tp (&__arr)[_Nm]) noexcept
      |     ^~~~~
/usr/include/c++/14/bits/range_access.h:95:5: note:   template argument deduction/substitution failed:
a.cc:11:18: note:   variable-sized array type 'long int' is not a valid template argument
   11 |   sort(std::begin(a), std::end(a));
      |        ~~~~~~~~~~^~~
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:166:
/usr/include/c++/14/valarray:1227:5: note: candidate: 'template<class _Tp> _Tp* std::begin(valarray<_Tp>&)'
 1227 |     begin(valarray<_Tp>& __va) noexcept
      |     ^~~~~
/usr/include/c++/14/valarray:1227:5: note:   template argument deduction/substitution failed:
a.cc:11:18: note:   mismatched types 'std::valarray<_Tp>' and 'int [n]'
   11 |   sort(std::begin(a), std::end(a));
      |        ~~~~~~~~~~^~~
/usr/include/c++/14/valarray:1238:5: note: candidate: 'template<class _Tp> const _Tp* std::begin(const valarray<_Tp>&)'
 1238 |     begin(const valarray<_Tp>& __va) noexcept
      |     ^~~~~
/usr/include/c++/14/valarray:1238:5: note:   template argument deduction/substitution failed:
a.cc:11:18: note:   mismatched types 'const std::valarray<_Tp>' and 'int [n]'
   11 |   sort(std::begin(a), std::end(a));
      |        ~~~~~~~~~~^~~
a.cc:11:31: error: no matching function for call to 'end(int [n])'
   11 |   sort(std::begin(a), std::end(a));
      |                       ~~~~~~~~^~~
/usr/include/c++/14/initializer_list:99:5: note: candidate: 'template<class _Tp> constexpr const _Tp* std::end(initializer_list<_Tp>)'
   99 |     end(initializer_list<_Tp> __ils) noexcept
      |     ^~~
/usr/include/c++/14/initializer_list:99:5: note:   template argument deduction/substitution failed:
a.cc:11:31: note:   mismatched types 'std::initializer_list<_Tp>' and 'int*'
   11 |   sort(std::begin(a), std::end(a));
      |                       ~~~~~~~~^~~
/usr/include/c++/14/bits/range_access.h:74:5: note: candidate: 'template<class _Container> constexpr decltype (__cont.end()) std::end(_Container&)'
   74 |     end(_Container& __cont) -> decltype(__cont.end())
      |     ^~~
/usr/include/c++/14/bits/range_access.h:74:5: note:   template argument deduction/substitution failed:
a.cc:11:31: note:   variable-sized array type 'int [n]' is not a valid template argument
   11 |   sort(std::begin(a), std::end(a));
      |                       ~~~~~~~~^~~
/usr/include/c++/14/bits/range_access.h:85:5: note: candidate: 'template<class _Container> constexpr decltype (__cont.end()) std::end(const _Container&)'
   85 |     end(const _Container& __cont) -> decltype(__cont.end())
      |     ^~~
/usr/include/c++/14/bits/range_access.h:85:5: note:   template argument deduction/substitution failed:
a.cc:11:31: note:   variable-sized array type 'int [n]' is not a valid template argument
   11 |   sort(std::begin(a), std::end(a));
      |                       ~~~~~~~~^~~
/usr/include/c++/14/bits/range_access.h:106:5: note: candidate: 'template<class _Tp, long unsigned int _Nm> constexpr _Tp* std::end(_Tp (&)[_Nm])'
  106 |     end(_Tp (&__arr)[_Nm]) noexcept
      |     ^~~
/usr/include/c++/14/bits/range_access.h:106:5: note:   template argument deduction/substitution failed:
a.cc:11:31: note:   variable-sized array type 'long int' is not a valid template argument
   11 |   sort(std::begin(a), std::end(a));
      |                       ~~~~~~~~^~~
/usr/include/c++/14/valarray:1249:5: note: candidate: 'template<class _Tp> _Tp* std::end(valarray<_Tp>&)'
 1249 |     end(valarray<_Tp>& __va) noexcept
      |     ^~~
/usr/include/c++/14/valarray:1249:5: note:   template argument deduction/substitution failed:
a.cc:11:31: note:   mismatched types 'std::valarray<_Tp>' and 'int [n]'
   11 |   sort(std::begin(a), std::end(a));
      |                       ~~~~~~~~^~~
/usr/include/c++/14/valarray:1265:5: note: candidate: 'template<class _Tp> const _Tp* std::end(const valarray<_Tp>&)'
 1265 |     end(const valarray<_Tp>& __va) noexcept
      |     ^~~
/usr/include/c++/14/valarray:1265:5: note:   template argument deduction/substitution failed:
a.cc:11:31: note:   mismatched types 'const std::valarray<_Tp>' and 'int [n]'
   11 |   sort(std::begin(a), std::end(a));
      |                       ~~~~~~~~^~~