中序遍歷(遞歸實現)
public void traversal(TreeNode root){
if(root != null){
//中序遍歷: 左、中、右
traversal(root.left);
System.out.println(root.val);
traversal(root.right);
}
}
中序遍歷(非遞歸實現)
public void traversal(TreeNode node){
while(node != null||!stack.empty()){
while(node != null){
stack.push(node);
node = node.left;
}
if(!stack.empty()){
node = stack.pop();
System.out.println(node.val);
node = node.right;
}
}
}