Language: C++

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

int main(){
  int N, K; cin >> N >> K;
  vector<long long> a(N);
  for(int i = 0; i < N; i++){
    cin >> a[i];
  }
  long long ans = 1e18;
  for(int i = 0; i < 1 << (N - 1); i++){
    int cnt = 0;
    for(int j=0;j < N-1;j++){
      cnt += (i>>j)&1;
    }
    if(cnt != K-1)continue;
    long long tmp = 0;
    long now = a[0];
    for(int j = 0; j < N - 1; j++){
      if(i>>j&1){
        if(now >= a[j + 1]){
          tmp += now - a[j + 1] + 1;
          now = max(now + 1, a[j + 1]);
        }
        now = max(now, a[j + 1]);
      }
    }
    ans = min(ans, tmp);
  }
  cout << ans << endl;
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:24:20: error: no matching function for call to 'max(long int, __gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type&)'
   24 |           now = max(now + 1, a[j + 1]);
      |                 ~~~^~~~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_algobase.h:257:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::max(const _Tp&, const _Tp&)'
  257 |     max(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note:   template argument deduction/substitution failed:
a.cc:24:20: note:   deduced conflicting types for parameter 'const _Tp' ('long int' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'})
   24 |           now = max(now + 1, a[j + 1]);
      |                 ~~~^~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare)'
  303 |     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note:   candidate expects 3 arguments, 2 provided
In file included from /usr/include/c++/14/algorithm:61:
/usr/include/c++/14/bits/stl_algo.h:5706:5: note: candidate: 'template<class _Tp> constexpr _Tp std::max(initializer_list<_Tp>)'
 5706 |     max(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5706:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::max(initializer_list<_Tp>, _Compare)'
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note:   template argument deduction/substitution failed:
a.cc:24:20: note:   mismatched types 'std::initializer_list<_Tp>' and 'long int'
   24 |           now = max(now + 1, a[j + 1]);
      |                 ~~~^~~~~~~~~~~~~~~~~~~
a.cc:26:18: error: no matching function for call to 'max(long int&, __gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type&)'
   26 |         now = max(now, a[j + 1]);
      |               ~~~^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::max(const _Tp&, const _Tp&)'
  257 |     max(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note:   template argument deduction/substitution failed:
a.cc:26:18: note:   deduced conflicting types for parameter 'const _Tp' ('long int' and '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'})
   26 |         now = max(now, a[j + 1]);
      |               ~~~^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare)'
  303 |     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note:   candidate expects 3 arguments, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5706:5: note: candidate: 'template<class _Tp> constexpr _Tp std::max(initializer_list<_Tp>)'
 5706 |     max(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5706:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::max(initializer_list<_Tp>, _Compare)'
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note:   template argument deduction/substitution failed:
a.cc:26:18: note:   mismatched types 'std::initializer_list<_Tp>' and 'long int'
   26 |         now = max(now, a[j + 1]);
      |               ~~~^~~~~~~~~~~~~~~