foo.c:3:6: error: 'binary' declared as function returning a function
    3 | void binary(n)(int n){
      |      ^~~~~~
foo.c: In function 'binary':
foo.c:3:6: warning: type of 'n' defaults to 'int' [-Wimplicit-int]
foo.c: At top level:
foo.c:9:1: warning: return type defaults to 'int' [-Wimplicit-int]
    9 | main()
      | ^~~~
foo.c: In function 'binary':
foo.c:7:1: warning: control reaches end of non-void function [-Wreturn-type]
    7 | }
      | ^

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