foo.cc: In function 'int main()':
foo.cc:16:13: error: 'cout' was not declared in this scope
   16 |             cout<<"Yes";
      |             ^~~~
foo.cc:18:13: error: 'cout' was not declared in this scope
   18 |             cout<<"No";
      |             ^~~~
foo.cc:6:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |     scanf("%d", &n);
      |     ~~~~~^~~~~~~~~~

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