foo.cc: In function 'int printNode(int)':
foo.cc:56:1: warning: no return statement in function returning non-void [-Wreturn-type]
   56 | }
      | ^
foo.cc:22:5: warning: infinite recursion detected [-Winfinite-recursion]
   22 | int printNode(int n) {
      |     ^~~~~~~~~
foo.cc:43:26: note: recursive call
   43 |                 printNode(lRealIdx);
      |                 ~~~~~~~~~^~~~~~~~~~
foo.cc:50:26: note: recursive call
   50 |                 printNode(rRealIdx);
      |                 ~~~~~~~~~^~~~~~~~~~

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