foo.c: In function 'main':
foo.c:24:17: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
   24 |         scanf("%d", a);
      |                ~^   ~
      |                 |   |
      |                 |   int
      |                 int *
foo.c:27:17: warning: format '%c' expects argument of type 'char *', but argument 2 has type 'int (*)[1]' [-Wformat=]
   27 |         scanf("%c", &arr);
      |                ~^   ~~~~
      |                 |   |
      |                 |   int (*)[1]
      |                 char *

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