title: A algorithm problem of complete two binary tree
body: <p>A complete binary tree with a maximum depth of 16 is known, with all leaf nodes having the same depth. If a small ball is placed at the root node, the ball will begin to fall along the root node. There is a switch on each node in the complete binary tree. The default is all off. When the ball falls, the state of the switch changes whenever a ball falls on a switch. When the ball reaches a node, if the switch on the node is closed, go to the left to go to the ball, otherwise go to the right until it reaches the leaf node. Please help me find the leaf node number after the 12345th ball fell.</p>