foo.cc: In function 'void dts::main()':
foo.cc:27:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   27 |         scanf("%d",&n);
      |         ~~~~~^~~~~~~~~
foo.cc:29:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   29 |             scanf("%d%d",&s[i].l,&s[i].r);
      |             ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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