foo.cc: In function 'void dts::main()':
foo.cc:19:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   19 |         scanf("%d%d",&n,&m);
      |         ~~~~~^~~~~~~~~~~~~~
foo.cc:21:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |             scanf("%d",&a[i]);
      |             ~~~~~^~~~~~~~~~~~

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