foo.cc: In function 'void dts::main()':
foo.cc:75:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   75 | scanf("%lld",&rec[i]);
      | ~~~~~^~~~~~~~~~~~~~~~
foo.cc:76:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   76 | scanf("%lld%lld",&a,&b);
      | ~~~~~^~~~~~~~~~~~~~~~~~

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