Language: C++

#include <iostream>
#include <algorithm>
using namespace std;

long long digitsum(long long b, long long n) {
    long long result = 0;
    while (n > 0) {
        result += n % b;
        n /= b;
    }
    return result;
}

int main() {
    long long n, s;
    unsigned long long result = -1;
    cin >> n >> s;
    for (long long b = 2; b * b <= n; b++) {
        if (digitsum(b, n) == s) {
            result = b;
            break;
        }
    }
    for (long long b = 2; b * b <= n - s; b++) {
        if ((n - s) % b == 0) {
            if (digitsum((n - s) / b, n) == s) {
                result = min(result, (n - s) / b);
            }
            if (digitsum(b, n) == s) {
                result = min(result, b);
            }
        }
    }
    if (digitsum(n - s, n) == s) {
        result = min(result, n - s);
    }
    if (s == 1) {
        result = min(result, n);
    }
    cout << result;
    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:27:29: error: no matching function for call to 'min(long long unsigned int&, long long int)'
   27 |                 result = min(result, (n - s) / b);
      |                          ~~~^~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/14/string:51,
                 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_algobase.h:233:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::min(const _Tp&, const _Tp&)'
  233 |     min(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:233:5: note:   template argument deduction/substitution failed:
a.cc:27:29: note:   deduced conflicting types for parameter 'const _Tp' ('long long unsigned int' and 'long long int')
   27 |                 result = min(result, (n - s) / b);
      |                          ~~~^~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:281:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::min(const _Tp&, const _Tp&, _Compare)'
  281 |     min(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:281:5: note:   candidate expects 3 arguments, 2 provided
In file included from /usr/include/c++/14/algorithm:61,
                 from a.cc:2:
/usr/include/c++/14/bits/stl_algo.h:5686:5: note: candidate: 'template<class _Tp> constexpr _Tp std::min(initializer_list<_Tp>)'
 5686 |     min(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5686:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5696:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::min(initializer_list<_Tp>, _Compare)'
 5696 |     min(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5696:5: note:   template argument deduction/substitution failed:
a.cc:27:29: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long unsigned int'
   27 |                 result = min(result, (n - s) / b);
      |                          ~~~^~~~~~~~~~~~~~~~~~~~~
a.cc:30:29: error: no matching function for call to 'min(long long unsigned int&, long long int&)'
   30 |                 result = min(result, b);
      |                          ~~~^~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:233:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::min(const _Tp&, const _Tp&)'
  233 |     min(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:233:5: note:   template argument deduction/substitution failed:
a.cc:30:29: note:   deduced conflicting types for parameter 'const _Tp' ('long long unsigned int' and 'long long int')
   30 |                 result = min(result, b);
      |                          ~~~^~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:281:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::min(const _Tp&, const _Tp&, _Compare)'
  281 |     min(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:281:5: note:   candidate expects 3 arguments, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5686:5: note: candidate: 'template<class _Tp> constexpr _Tp std::min(initializer_list<_Tp>)'
 5686 |     min(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5686:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5696:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::min(initializer_list<_Tp>, _Compare)'
 5696 |     min(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5696:5: note:   template argument deduction/substitution failed:
a.cc:30:29: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long unsigned int'
   30 |                 result = min(result, b);
      |                          ~~~^~~~~~~~~~~
a.cc:35:21: error: no matching function for call to 'min(long long unsigned int&, long long int)'
   35 |         result = min(result, n - s);
      |                  ~~~^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:233:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::min(const _Tp&, const _Tp&)'
  233 |     min(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:233:5: note:   template argument deduction/substitution failed:
a.cc:35:21: note:   deduced conflicting types for parameter 'const _Tp' ('long long unsigned int' and 'long long int')
   35 |         result = min(result, n - s);
      |                  ~~~^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:281:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::min(const _Tp&, const _Tp&, _Compare)'
  281 |     min(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:281:5: note:   candidate expects 3 arguments, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5686:5: note: candidate: 'template<class _Tp> constexpr _Tp std::min(initializer_list<_Tp>)'
 5686 |     min(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5686:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5696:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::min(initializer_list<_Tp>, _Compare)'
 5696 |     min(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5696:5: note:   template argument deduction/substitution failed:
a.cc:35:21: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long unsigned int'
   35 |         result = min(result, n - s);
      |                  ~~~^~~~~~~~~~~~~~~
a.cc:38:21: error: no matching function for call to 'min(long long unsigned int&, long long int&)'
   38 |         result = min(result, n);
      |                  ~~~^~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:233:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::min(const _Tp&, const _Tp&)'
  233 |     min(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:233:5: note:   template argument deduction/substitution failed:
a.cc:38:21: note:   deduced conflicting types for parameter 'const _Tp' ('long long unsigned int' and 'long long int')
   38 |         result = min(result, n);
      |                  ~~~^~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:281:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::min(const _Tp&, const _Tp&, _Compare)'
  281 |     min(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:281:5: note:   candidate expects 3 arguments, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5686:5: note: candidate: 'template<class _Tp> constexpr _Tp std::min(initializer_list<_Tp>)'
 5686 |     min(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5686:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5696:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::min(initializer_list<_Tp>, _Compare)'
 5696 |     min(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5696:5: note:   template argument deduction/substitution failed:
a.cc:38:21: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long unsigned int'
   38 |         result = min(result, n);
      |                  ~~~^~~~~~~~~~~