foo.cc: In function 'int main()':
foo.cc:14:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   14 | scanf("%s",al);
      | ~~~~~^~~~~~~~~
foo.cc:15:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   15 | scanf("%s",bl);
      | ~~~~~^~~~~~~~~
foo.cc:17:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 | scanf("%d",&k);
      | ~~~~~^~~~~~~~~

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