foo.cc: In function 'int main()':
foo.cc:15:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   15 | scanf( "%d %d" , &n , &k );
      | ~~~~~^~~~~~~~~~~~~~~~~~~~~
foo.cc:19:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   19 | scanf( "%d" , &s[j] );
      | ~~~~~^~~~~~~~~~~~~~~~

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