foo.cc: In function 'int Input(int*, int)':
foo.cc:8:1: warning: no return statement in function returning non-void [-Wreturn-type]
    8 | }
      | ^
foo.cc: In function 'int Output(int*, int)':
foo.cc:13:1: warning: no return statement in function returning non-void [-Wreturn-type]
   13 | }
      | ^

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