foo.c:2:10: error: expected ')' before 'j'
    2 | int (Aint j)
      |          ^~
      |          )
foo.c: In function 'A2':
foo.c:19:6: warning: implicit declaration of function 'A'; did you mean 'A2'? [-Wimplicit-function-declaration]
   19 |   if(A(a)==1)
      |      ^
      |      A2
foo.c: In function 'main':
foo.c:33:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   33 |  scanf("%d",&x);
      |  ^~~~~~~~~~~~~~

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