foo.cc: In function 'bool check2(int)':
foo.cc:18:38: error: expected ';' before 'return'
   18 |                 aa[i] = (aa[i] - 'a')
      |                                      ^
      |                                      ;
   19 |         return 1;
      |         ~~~~~~                        
foo.cc:20:1: warning: no return statement in function returning non-void [-Wreturn-type]
   20 | }
      | ^

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