foo.cc: In function 'int main()':
foo.cc:36:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   36 | scanf("%d",&n);
      | ~~~~~^~~~~~~~~
foo.cc:38:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   38 | scanf("%d%d%d%d",&x1[i],&ydown[i],&x2[i],&y2[i]);
      | ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:39:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   39 | scanf("%d%d%d%d",&stx,&sty,&edx,&edy);
      | ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:45:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   45 | scanf("%lf",&v);
      | ~~~~~^~~~~~~~~~

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