foo.cc: In function 'void BubbleSort(int*, int)':
foo.cc:13:3: error: 'Output' was not declared in this scope
   13 |   Output(a,n);
      |   ^~~~~~
foo.cc: In function 'void Output(int*, int)':
foo.cc:19:3: error: 'cout' was not declared in this scope
   19 |   cout<<a[i]<<" ";
      |   ^~~~
foo.cc:20:2: error: 'cout' was not declared in this scope
   20 |  cout<<endl;
      |  ^~~~
foo.cc:20:8: error: 'endl' was not declared in this scope
   20 |  cout<<endl;
      |        ^~~~

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