foo.cc: In function 'int main()':
foo.cc:34:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   34 |     scanf("%d %d", &C, &R);
      |     ~~~~~^~~~~~~~~~~~~~~~~
foo.cc:39:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   39 |             scanf("%c", &ch);
      |             ~~~~~^~~~~~~~~~~

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