foo.c: In function 'main':
foo.c:7:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
    7 |  scanf("%s",&a);
      |         ~^  ~~
      |          |  |
      |          |  char (*)[100]
      |          char *
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%s",&a);
      |  ^~~~~~~~~~~~~~

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