(self, root)
| 46 | return True |
| 47 | # modify iterative(BFS) |
| 48 | def isSymmetric_2(self, root): |
| 49 | if root: |
| 50 | nodeStack = [root] |
| 51 | while nodeStack: |
| 52 | vals = [node.val if node else None for node in nodeStack] |
| 53 | if list(reversed(vals)) != vals: |
| 54 | return False |
| 55 | else: |
| 56 | preStack = [node for node in nodeStack if node] |
| 57 | nodeStack = [] |
| 58 | for preNode in preStack: |
| 59 | nodeStack.append(preNode.left) |
| 60 | nodeStack.append(preNode.right) |
| 61 | return True |
| 62 | |
| 63 | # iterative(DFS) |
| 64 | def isSymmetric3(self, root): |
nothing calls this directly
no outgoing calls
no test coverage detected