foo.cc: In function 'int main()':
foo.cc:9:7: warning: unused variable 'c' [-Wunused-variable]
    9 |  char c;
      |       ^
foo.cc:13:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |   scanf(" ");
      |   ~~~~~^~~~~

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