Driver code
let root = newnode ( 10 ) ; root . right = newnode ( 50 ) ; root . right . right = newnode ( 15 ) ; root . left = newnode ( 20 ) ; root . left . left = newnode ( 50 ) ; root . left . right = newnode ( 23 ) ; root . right . left = newnode ( 10 ) ; func ( root ) ;