foo.cc: In function 'int main()':
foo.cc:22:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   22 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:26:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   26 |   scanf("%d%d",&u,&v);
      |   ~~~~~^~~~~~~~~~~~~~
foo.cc:34:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   34 |  scanf("%d%d",&u,&v);
      |  ~~~~~^~~~~~~~~~~~~~

Found 5 testcases.
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