foo.cc:16:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   16 | main()
      |      ^
foo.cc: In function 'int main()':
foo.cc:18:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |  scanf("%lld",&n);
      |  ~~~~~^~~~~~~~~~~
foo.cc:21:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |   scanf("%lld %lld",&f[i].a,&f[i].b);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Found 10 testcases.
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