foo.cc: In function 'int main()':
foo.cc:7:13: warning: format '%s' expects argument of type 'char*', but argument 2 has type 'char (*)[200]' [-Wformat=]
    7 |     scanf("%s",&a);
      |            ~^  ~~
      |             |  |
      |             |  char (*)[200]
      |             char*
foo.cc:7:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    7 |     scanf("%s",&a);
      |     ~~~~~^~~~~~~~~

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