View Compilation Error

0_0_38917382_4027.cpp: In function 'std::string getstring(std::string)':
0_0_38917382_4027.cpp:38:40: error: reference to 'sample' is ambiguous
   38 |             int index = s.find_last_of(sample,i);
      |                                        ^~~~~~
In file included from gcc-13.1.0/lib/gcc/x86_64-w64-mingw32/13.1.0/include/c++/algorithm:61,
                 from 0_0_38917382_4027.cpp:4:
gcc-13.1.0/lib/gcc/x86_64-w64-mingw32/13.1.0/include/c++/bits/stl_algo.h:5915:5: note: candidates are: 'template<class _PopulationIterator, class _SampleIterator, class _Distance, class _UniformRandomBitGenerator> _SampleIterator std::sample(_PopulationIterator, _PopulationIterator, _SampleIterator, _Distance, _UniformRandomBitGenerator&&)'
 5915 |     sample(_PopulationIterator __first, _PopulationIterator __last,
      |     ^~~~~~
0_0_38917382_4027.cpp:15:14: note:                 'const std::string sample'
   15 | const string sample = "+-*/()";
      |              ^~~~~~