foo.c: In function 'main':
foo.c:11:9: error: 'return0' undeclared (first use in this function)
   11 |         return0
      |         ^~~~~~~
foo.c:11:9: note: each undeclared identifier is reported only once for each function it appears in
foo.c:11:16: error: expected ';' before '}' token
   11 |         return0
      |                ^
      |                ;
   12 | }
      | ~               

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