foo.cc: In function 'int main()':
foo.cc:13:10: error: 'n' was not declared in this scope; did you mean 'yn'?
   13 |     cin>>n;
      |          ^
      |          yn
foo.cc: In function 'int x(int)':
foo.cc:10:1: warning: control reaches end of non-void function [-Wreturn-type]
   10 | }
      | ^

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