foo.cc: In function 'int main()':
foo.cc:16:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   16 |  scanf("%c",&c);
      |  ~~~~~^~~~~~~~~
foo.cc:20:11: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   20 |      scanf("%c",&c);
      |      ~~~~~^~~~~~~~~

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