foo.cc: In function 'int main()':
foo.cc:10:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |         for(int i=0;i<s.size();i++)
      |                     ~^~~~~~~~~
foo.cc:14:34: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   14 |                         if(w>='A'&&w<='Z'||w>='a'&&w<='z')
      |                            ~~~~~~^~~~~~~~

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