foo.cc: In function 'int main()':
foo.cc:13:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |         for(int i=0;i<s.size();i++)
      |                     ~^~~~~~~~~
foo.cc:17:30: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   17 |                 if(a==11&&a>b&&a-b>=2||b==11&&b>a&&b-a>=2)
      |                    ~~~~~~~~~~^~~~~~~~
foo.cc:22:35: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   22 |                 else if(a>=11&&a>b&&a-b>=2||b>=11&&b>a&&b-a>=2)
      |                         ~~~~~~~~~~^~~~~~~~
foo.cc:30:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |         for(int i=0;i<s.size();i++)
      |                     ~^~~~~~~~~
foo.cc:34:30: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   34 |                 if(a==21&&a>b&&a-b>=2||b==21&&b>a&&b-a>=2)
      |                    ~~~~~~~~~~^~~~~~~~
foo.cc:39:35: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   39 |                 else if(a>=21&&a>b&&a-b>=2||b>=21&&b>a&&b-a>=2)
      |                         ~~~~~~~~~~^~~~~~~~

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