foo.cc: In function 'int main()':
foo.cc:68:11: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   68 |      scanf("%lld",&tt);
      |      ~~~~~^~~~~~~~~~~~
foo.cc:71:15: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   71 |          scanf("%lld%lld",&n,&m);
      |          ~~~~~^~~~~~~~~~~~~~~~~~
foo.cc:76:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   76 |              scanf("%lld",&x);
      |              ~~~~~^~~~~~~~~~~
foo.cc:81:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   81 |              scanf("%lld%lld",&x,&y);
      |              ~~~~~^~~~~~~~~~~~~~~~~~

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