Language: C++

#include <bits/stdc++.h>
#include <string>
using namespace std;
int main(void){
	int sum;
  	string s;
  	scanf("%s",&s);
  	sum = search(s);
  	printf("%d", sum);
  	return 0;
}
int search(string s){
	int i,sum;
  	sum = 0;
  	string s2,s3;
  	for (i=0;i<s.size();i++){
      	s2 = str.substr(0,i);
      	s3 = str.substr(i);
      	sum += (int)(s2) + search(s3);
    }
  	return sum;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:8:21: error: no matching function for call to 'search(std::string&)'
    8 |         sum = search(s);
      |               ~~~~~~^~~
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:2332:5: note: candidate: 'template<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate> _ForwardIterator1 std::search(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2, _BinaryPredicate)'
 2332 |     search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
      |     ^~~~~~
/usr/include/c++/14/bits/stl_algobase.h:2332:5: note:   candidate expects 5 arguments, 1 provided
In file included from /usr/include/c++/14/algorithm:61:
/usr/include/c++/14/bits/stl_algo.h:4090:5: note: candidate: 'template<class _FIter1, class _FIter2> _FIter1 std::search(_FIter1, _FIter1, _FIter2, _FIter2)'
 4090 |     search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
      |     ^~~~~~
/usr/include/c++/14/bits/stl_algo.h:4090:5: note:   candidate expects 4 arguments, 1 provided
/usr/include/c++/14/bits/stl_algo.h:4184:5: note: candidate: 'template<class _ForwardIterator, class _Searcher> _ForwardIterator std::search(_ForwardIterator, _ForwardIterator, const _Searcher&)'
 4184 |     search(_ForwardIterator __first, _ForwardIterator __last,
      |     ^~~~~~
/usr/include/c++/14/bits/stl_algo.h:4184:5: note:   candidate expects 3 arguments, 1 provided
In file included from /usr/include/c++/14/algorithm:86:
/usr/include/c++/14/pstl/glue_algorithm_defs.h:112:1: note: candidate: 'template<class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate> __pstl::__internal::__enable_if_execution_policy<_ExecutionPolicy, _ForwardIterator> std::search(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2, _BinaryPredicate)'
  112 | search(_ExecutionPolicy&& __exec, _ForwardIterator1 __first, _ForwardIterator1 __last, _ForwardIterator2 __s_first,
      | ^~~~~~
/usr/include/c++/14/pstl/glue_algorithm_defs.h:112:1: note:   candidate expects 6 arguments, 1 provided
/usr/include/c++/14/pstl/glue_algorithm_defs.h:117:1: note: candidate: 'template<class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2> __pstl::__internal::__enable_if_execution_policy<_ExecutionPolicy, _ForwardIterator> std::search(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2)'
  117 | search(_ExecutionPolicy&& __exec, _ForwardIterator1 __first, _ForwardIterator1 __last, _ForwardIterator2 __s_first,
      | ^~~~~~
/usr/include/c++/14/pstl/glue_algorithm_defs.h:117:1: note:   candidate expects 5 arguments, 1 provided
a.cc: In function 'int search(std::string)':
a.cc:17:14: error: 'str' was not declared in this scope; did you mean 'std'?
   17 |         s2 = str.substr(0,i);
      |              ^~~
      |              std
a.cc:19:16: error: invalid cast from type 'std::string' {aka 'std::__cxx11::basic_string<char>'} to type 'int'
   19 |         sum += (int)(s2) + search(s3);
      |                ^~~~~~~~~