foo.cc: In function 'int main()':
foo.cc:71:8: warning: unused variable 'ans' [-Wunused-variable]
   71 |     ll ans=0;
      |        ^~~
foo.cc:72:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   72 |     scanf("%lld",&n);
      |     ~~~~~^~~~~~~~~~~
foo.cc:77:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   77 |         scanf("%lld%lld%lld",&x1,&x2,&y2);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

Found 10 testcases.
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