foo.c: In function 'main':
foo.c:41:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10001]' [-Wformat=]
  scanf("%s",&a);
         ~^  ~~
foo.c:42:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10001]' [-Wformat=]
  scanf("%s",&b);
         ~^  ~~
foo.c:41:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s",&a);
  ^~~~~~~~~~~~~~
foo.c:42:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s",&b);
  ^~~~~~~~~~~~~~

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