foo.cc: In function 'int main()':
foo.cc:29:67: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   29 |             if(Q[Pos]==']'&&Q.find(":")!=string::npos&&Q.find(":")<Pos-1)
      |                                                        ~~~~~~~~~~~^~~~~~

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