foo.cc:3:1: error: '::main' must return 'int'
    3 | void main()
      | ^~~~
foo.cc: In function 'int main()':
foo.cc:8:17: error: expected ';' before '}' token
    8 |         return 0
      |                 ^
      |                 ;
    9 | }
      | ~                

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