foo.c: In function 'main':
foo.c:7:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[9]' [-Wformat=]
    7 |     scanf("%s", &a);
      |            ~^   ~~
      |             |   |
      |             |   char (*)[9]
      |             char *
foo.c:8:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[9]' [-Wformat=]
    8 |     scanf("%s", &b);
      |            ~^   ~~
      |             |   |
      |             |   char (*)[9]
      |             char *
foo.c:7:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |     scanf("%s", &a);
      |     ^~~~~~~~~~~~~~~
foo.c:8:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |     scanf("%s", &b);
      |     ^~~~~~~~~~~~~~~

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