foo.c: In function 'main':
foo.c:9:17: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
    9 |         scanf("%d",n);
      |                ~^  ~
      |                 |  |
      |                 |  int
      |                 int *
foo.c:9:9: warning: 'n' is used uninitialized [-Wuninitialized]
    9 |         scanf("%d",n);
      |         ^~~~~~~~~~~~~
foo.c:17:9: warning: 'num' may be used uninitialized in this function [-Wmaybe-uninitialized]
   17 |         printf("%d",num);
      |         ^~~~~~~~~~~~~~~~

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