foo.cc: In function 'void dts::main()':
foo.cc:12:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   12 |         scanf("%lld",&n);
      |         ~~~~~^~~~~~~~~~~
foo.cc:14:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   14 |             scanf("%lld",&a[i]);
      |             ~~~~~^~~~~~~~~~~~~~

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