/in/foo.cc: In function 'int myAtoi(std::__cxx11::string)':
/in/foo.cc:7:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<s.size();i++)
              ~^~~~~~~~~
/in/foo.cc:15:5: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
   if(s[i]>='0'&&s[i]<='9')
     ^