foo.cc: In function 'int getLong(std::__cxx11::string&)':
foo.cc:15:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < str.length(); i++) {
                  ~~^~~~~~~~~~~~~~
foo.cc: In function 'int getAns(std::__cxx11::string&)':
foo.cc:27:10: error: 'pow' was not declared in this scope
  int t = pow(2, m + 1);
          ^~~
foo.cc:27:10: note: suggested alternative: 'putw'
  int t = pow(2, m + 1);
          ^~~
          putw

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