foo.cc: In function 'int main()':
foo.cc:48:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   48 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
foo.cc:50:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   50 |         scanf("%d%d",&u,&v);
      |         ~~~~~^~~~~~~~~~~~~~

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Found 10 testcases.
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