def cloneTree(root: TreeNode) -> TreeNode:
if root:
newRoot = TreeNode(root.val)
newRoot.left = cloneTree(root.left)
newRoot.right = cloneTree(root.right)
return newRoot
return None
def convertBSTImpl(root: TreeNode, v: int) -> (TreeNode, int):
if not root:
return None, 0
newRight, sumRight = convertBSTImpl(root.right, v)
newRoot = TreeNode(root.val + sumRight + v)
newLeft, sumLeft = convertBSTImpl(root.left, newRoot.val)
newRoot.left = newLeft
newRoot.right = newRight
return newRoot, sumLeft + root.val + sumRight
def sortedArrayToBSTImpl(nums: List[int], l, r: int):
cnt = r - l
if cnt == 0:
return None
if cnt == 1:
return TreeNode(nums[l])
m = l + cnt // 2
return TreeNode(nums[m], sortedArrayToBSTImpl(nums, l, m),
sortedArrayToBSTImpl(nums, m + 1, r))
def trimBST(self, root: TreeNode, low: int, high: int) -> TreeNode:
if not root:
return None
if root.val > high:
return self.trimBST(root.left, low, high)
if root.val < low:
return self.trimBST(root.right, low, high)
root.left = self.trimBST(root.left, low, high)
root.right = self.trimBST(root.right, low, high)
return root
def helper(beg: int, end: int) -> TreeNode:
if beg > end:
return None
mid = beg + (end - beg) // 2
left = helper(beg, mid - 1)
root = TreeNode(self.head.val)
self.head = self.head.next
root.left = left
root.right = helper(mid + 1, end)
return root
def impl(pre_b: int, pre_e: int, in_b: int, in_e: int) -> TreeNode:
if pre_b == pre_e:
return None
val = preorder[pre_b]
root = TreeNode(val)
m = inorder_index[val]
left_end = pre_b + 1 + m - in_b
root.left = impl(pre_b + 1, left_end, in_b, m)
root.right = impl(left_end, pre_e, m + 1, in_e)
return root
def impl(root: TreeNode) -> TreeNode:
if not root:
return None
left_end = impl(root.left)
right_end = impl(root.right)
right = root.right
root.right = root.left
root.left = None
if left_end:
left_end.right = right
else:
root.right = right
if right_end:
return right_end
if left_end:
return left_end
return root
def addOneRow(self, root: TreeNode, v: int, d: int) -> TreeNode:
fakeRoot = TreeNode(0)
current = [[root, fakeRoot, 1]]
depth = 1
while depth < d:
next_level = []
for n, p, _ in current:
if n:
next_level.append([n.left, n, 1])
next_level.append([n.right, n, 2])
depth += 1
current = next_level
for n, p, x in current:
if p:
if x == 1:
p.left = TreeNode(v, n)
elif x == 2:
p.right = TreeNode(v, None, n)
return root if d > 1 else fakeRoot.left
if root is None:
return 0
dl = dr = 0
if root.left:
dl = self.minDepth(root.left)
if root.right:
dr = self.minDepth(root.right)
if dl > 0 and dr > 0:
return 1 + min(dl, dr)
if dl > 0:
return dl + 1
return dr + 1
tree1 = TreeNode(3)
tree1.left = TreeNode(9)
tree1.right = TreeNode(20)
tree1.right.left = TreeNode(15)
tree1.right.right = TreeNode(7)
tree2 = TreeNode(1)
tree2.left = TreeNode(2)
tests = [(tree1, 2), (tree2, 2)]
run_functional_tests(Solution().minDepth, tests)
L = solve(root.left)
R = solve(root.right)
dp0 = L[1] + R[1]
dp1 = min(L[2] + min(R[1:]), R[2] + min(L[1:]))
dp2 = 1 + min(L[:]) + min(R[:])
return [dp0, dp1, dp2]
return min(solve(root)[1:])
tests = [
[
TreeNode(0,
TreeNode(0,
TreeNode(0),
TreeNode(0))),
1
],
[
TreeNode(0,
TreeNode(0,
TreeNode(0,
TreeNode(0,
null,
TreeNode(0))))),
2
],
[
TreeNode(0),
1
class Solution:
def subtreeWithAllDeepest(self, root: TreeNode) -> TreeNode:
def dfs(root: TreeNode) -> (TreeNode, int):
if root is None:
return root, 0
L = dfs(root.left)
R = dfs(root.right)
if L[1] > R[1]:
return L[0], L[1] + 1
if R[1] > L[1]:
return R[0], R[1] + 1
return root, L[1] + 1
return dfs(root)[0]
root = TreeNode(3)
root.left = TreeNode(5)
root.left.left = TreeNode(6)
root.left.right = TreeNode(2)
root.left.right.left = TreeNode(7)
root.left.right.right = TreeNode(4)
root.right = TreeNode(1)
root.right.left = TreeNode(0)
root.right.right = TreeNode(8)
tests = [(root, TreeNode(2, TreeNode(7), TreeNode(4)))]
run_functional_tests(Solution().subtreeWithAllDeepest, tests)
def rightSideView(self, root: TreeNode) -> List[int]:
levels = []
def rightSideViewImpl(root: TreeNode, level: int):
if not root:
return
nonlocal levels
if level == len(levels):
levels.append(root.val)
rightSideViewImpl(root.right, level+1)
rightSideViewImpl(root.left, level + 1)
rightSideViewImpl(root, 0)
return levels
root1 = TreeNode(1)
root1.left = TreeNode(2)
root1.right = TreeNode(3)
root1.left.right = TreeNode(5)
root1.right.right = TreeNode(4)
tests = [
(root1, [1, 3, 4])
]
run_functional_tests(Solution().rightSideView, tests)
class Solution:
def bstToGst(self, root: TreeNode) -> TreeNode:
def convertBSTImpl(root: TreeNode, v: int) -> (TreeNode, int):
if not root:
return None, 0
newRight, sumRight = convertBSTImpl(root.right, v)
newRoot = TreeNode(root.val + sumRight + v)
newLeft, sumLeft = convertBSTImpl(root.left, newRoot.val)
newRoot.left = newLeft
newRoot.right = newRight
return newRoot, sumLeft + root.val + sumRight
return convertBSTImpl(root, 0)[0]
root1 = TreeNode(4)
root1.left = TreeNode(1)
root1.right = TreeNode(6)
root1.left.left = TreeNode(0)
root1.left.right = TreeNode(2)
root1.left.right.right = TreeNode(3)
root1.right.left = TreeNode(5)
root1.right.right = TreeNode(7)
root1.right.right.right = TreeNode(8)
"""
30
(36
(36 ()
35
(33 ())
# Runtime: 32 ms, faster than 80.06% of Python3 online submissions for Binary Tree Level Order Traversal.
# Memory Usage: 15.2 MB, less than 12.67% of Python3 online submissions for Binary Tree Level Order Traversal.
class Solution:
def levelOrder(self, root: TreeNode) -> List[List[int]]:
levels = []
def traverse(root: TreeNode, level: int):
nonlocal levels
if not root:
return
if level >= len(levels):
levels.append([])
levels[level].append(root.val)
traverse(root.left, level + 1)
traverse(root.right, level + 1)
traverse(root, 0)
return levels
tests = [[
TreeNode(1, TreeNode(2, TreeNode(4), TreeNode(5)), TreeNode(3)),
[[1], [2, 3], [4, 5]]
],
[
TreeNode(3, TreeNode(9), TreeNode(20, TreeNode(15), TreeNode(7))),
[[3], [9, 20], [15, 7]]
], [TreeNode(1), [[1]]], [null, []]]
run_functional_tests(Solution().levelOrder, tests)
class Solution:
def getTargetCopy(self, original: TreeNode, cloned: TreeNode,
target: TreeNode) -> TreeNode:
if not original:
return None
if original is target:
return cloned
resultLeft = self.getTargetCopy(original.left, cloned.left, target)
if resultLeft:
return resultLeft
return self.getTargetCopy(original.right, cloned.right, target)
root1 = TreeNode(7)
root1.left = TreeNode(4)
root1.right = TreeNode(3)
root1.right.left = TreeNode(6)
root1.right.right = TreeNode(19)
print(Solution().getTargetCopy(root1, cloneTree(root1), root1.right).val) # 3
root2 = TreeNode(7)
print(Solution().getTargetCopy(root2, cloneTree(root2), root2).val) # 7
root3 = TreeNode(8)
root3.right = TreeNode(6)
root3.right.right = TreeNode(5)
root3.right.right.right = TreeNode(4)
"""
prev, first, second = None, None, None
def inorder(node: TreeNode):
nonlocal prev, first, second
if node.left:
inorder(node.left)
if not first and (not prev or node.val < prev.val):
first = prev
if first and (not prev or node.val < prev.val):
second = node
prev = node
if node.right:
inorder(node.right)
inorder(root)
first.val, second.val = second.val, first.val
tests = [[
TreeNode(1, TreeNode(3, null, TreeNode(2))),
TreeNode(3, TreeNode(1, null, TreeNode(2)))
],
[
TreeNode(3, TreeNode(1), TreeNode(4, TreeNode(2))),
TreeNode(2, TreeNode(1), TreeNode(4, TreeNode(3)))
]]
run_functional_tests(in_place_to_function(Solution().recoverTree), tests)
class Solution:
def trimBST(self, root: TreeNode, low: int, high: int) -> TreeNode:
if not root:
return None
if root.val > high:
return self.trimBST(root.left, low, high)
if root.val < low:
return self.trimBST(root.right, low, high)
root.left = self.trimBST(root.left, low, high)
root.right = self.trimBST(root.right, low, high)
return root
tests = [
(TreeNode(1, TreeNode(0),
TreeNode(2)), 1, 2, TreeNode(1, None, TreeNode(2))),
(TreeNode(3, TreeNode(0, None, TreeNode(2, TreeNode(1))),
TreeNode(4)), 1, 3, TreeNode(3, TreeNode(2, TreeNode(1)))),
]
def treesEqual(root1: TreeNode, root2: TreeNode) -> bool:
if not root1 and not root2:
return True
if not root1 or not root2:
return False
if root1.val != root2.val:
return False
if not treesEqual(root1.left, root2.left):
return False
return treesEqual(root1.right, root2.right)
self.move_first()
def next(self) -> int:
value = self.current.val
self.move_next()
return value
def hasNext(self) -> bool:
return self.current is not None
# Your BSTIterator object will be instantiated and called as such:
# obj = BSTIterator(root)
# param_1 = obj.next()
# param_2 = obj.hasNext()
root = TreeNode(5)
root.left = TreeNode(3)
root.left.right = TreeNode(4)
root.left.left = TreeNode(2)
root.right = TreeNode(7)
root.right.left = TreeNode(6)
# it = BSTIterator(root)
#
# while it.hasNext():
# print(it.next())
tests = [
(
["BSTIterator", "hasNext", "next", "hasNext", "next", "hasNext", "next", "hasNext", "next", "hasNext", "next", "hasNext", "next", "hasNext"],
[[root], [], [], [], [], [], [], [], [], [], [], null, null, null],
"""
class Solution:
def isSameTree(self, p: TreeNode, q: TreeNode) -> bool:
if p is None and q is None:
return True
if p is None or q is None:
return False
if p.val != q.val:
return False
return self.isSameTree(p.left, q.left) and self.isSameTree(
p.right, q.right)
tree1 = TreeNode(1)
tree1.left = TreeNode(2)
tree1.right = TreeNode(3)
tree2 = TreeNode(1)
tree2.left = TreeNode(2)
tree2.right = TreeNode(3)
print(Solution().isSameTree(tree1, tree2)) # True
tree1 = TreeNode(1)
tree1.left = TreeNode(2)
tree2 = TreeNode(1)
tree2.right = TreeNode(2)
next_level.append([n.right, n, 2])
depth += 1
current = next_level
for n, p, x in current:
if p:
if x == 1:
p.left = TreeNode(v, n)
elif x == 2:
p.right = TreeNode(v, None, n)
return root if d > 1 else fakeRoot.left
tests = [(TreeNode(1, TreeNode(2, TreeNode(4)), TreeNode(3)), 5, 4,
TreeNode(1, TreeNode(2, TreeNode(4, TreeNode(5), TreeNode(5))),
TreeNode(3))),
(
TreeNode(4, TreeNode(2, TreeNode(3), TreeNode(1)),
TreeNode(6, TreeNode(5))),
1,
1,
TreeNode(
1,
TreeNode(4, TreeNode(2, TreeNode(3), TreeNode(1)),
TreeNode(6, TreeNode(5)))),
),
(
TreeNode(4, TreeNode(2, TreeNode(3), TreeNode(1)),
TreeNode(6, TreeNode(5))),
# self.i = 0
#
# def dfs(node):
# if node:
# if node.val != voyage[self.i]:
# self.flipped = [-1]
# return
# self.i += 1
# if self.i < len(voyage) and node.left and node.left.val != voyage[self.i]:
# self.flipped.append(node.val)
# dfs(node.right)
# dfs(node.left)
# else:
# dfs(node.left)
# dfs(node.right)
#
# dfs(root)
# if self.flipped and self.flipped[0] == -1:
# self.flipped = [-1]
# return self.flipped
tests = [((TreeNode(1, TreeNode(5, TreeNode(7), TreeNode(2)),
TreeNode(6, TreeNode(4),
TreeNode(3)))), [1, 5, 2, 6, 3, 4, 7], [-1]),
(TreeNode(2, TreeNode(1, TreeNode(4), TreeNode(3))), [2, 1, 3,
4], [1]),
(TreeNode(1, TreeNode(2)), [2, 1], [-1]),
(TreeNode(1, TreeNode(2), TreeNode(3)), [1, 3, 2], [1]),
(TreeNode(1, TreeNode(2), TreeNode(3)), [1, 2, 3], [])]
run_functional_tests(Solution().flipMatchVoyage, tests)
nodes.append(current.val)
if not current.left and not current.right:
if len(nodes) <= 1:
result += 1
dfs(current.left)
dfs(current.right)
if current.val in nodes:
nodes.remove(current.val)
else:
nodes.append(current.val)
dfs(root)
return result
root1 = TreeNode(2)
root1.left = TreeNode(3)
root1.left.left = TreeNode(3)
root1.left.right = TreeNode(1)
root1.right = TreeNode(1)
root1.right.right = TreeNode(1)
# if Solution().pseudoPalindromicPaths(root1) == 2:
# print("PASS")
# else:
# print("FAIL")
root2 = TreeNode(2)
root2.left = TreeNode(1)
root2.left.left = TreeNode(1)
root2.left.right = TreeNode(3)
def averageOfLevels(self, root: TreeNode) -> List[float]:
levels = []
def walkLevels(root: TreeNode, level: int):
if not root:
return
nonlocal levels
if len(levels) <= level:
levels.append([root.val, 1])
else:
levels[level][0] += root.val
levels[level][1] += 1
walkLevels(root.left, level + 1)
walkLevels(root.right, level + 1)
walkLevels(root, 0)
return [s / c for s, c in levels]
root1 = TreeNode(3)
root1.left = TreeNode(9)
root1.right = TreeNode(20)
root1.right.left = TreeNode(15)
root1.right.right = TreeNode(7)
tests = [(root1, [3, 14.5, 11])]
run_functional_tests(Solution().averageOfLevels, tests)
path2: List[TreeNode] = self.getPath(root, q)
n1 = len(path1)
n2 = len(path2)
i1 = n1 - 1
i2 = n2 - 1
while i2 > i1:
i2 -= 1
while i1 > i2:
i1 -= 1
while path1[i1] is not path2[i2]:
i1 -= 1
i2 -= 1
return path2[i1]
t1 = TreeNode(6)
n1 = t1.left = TreeNode(2)
n2 = t1.right = TreeNode(8)
t1.left.left = TreeNode(0)
n3 = t1.left.right = TreeNode(4)
t1.left.right.left = TreeNode(3)
t1.left.right.right = TreeNode(5)
t1.right.left = TreeNode(7)
t1.right.right = TreeNode(9)
print(Solution().lowestCommonAncestor(t1, n1, n2).val) # 6
print(Solution().lowestCommonAncestor(t1, n1, n3).val) # 2
class Solution:
@staticmethod
def isLeave(root: TreeNode):
return root.left is None and root.right is None
def sumOfLeftLeavesImpl(self, root: TreeNode, isLeft: bool) -> int:
if Solution.isLeave(root):
return root.val if isLeft else 0
sumleft = sumright = 0
if root.left:
sumleft = self.sumOfLeftLeavesImpl(root.left, True)
if root.right:
sumright = self.sumOfLeftLeavesImpl(root.right, False)
return sumleft + sumright
def sumOfLeftLeaves(self, root: TreeNode) -> int:
if root is None:
return 0
return self.sumOfLeftLeavesImpl(root, False)
t1 = TreeNode(3)
t1.left = TreeNode(9)
t1.right = TreeNode(20)
t1.right.left = TreeNode(15)
t1.right.right = TreeNode(7)
print(Solution().sumOfLeftLeaves(t1)) # 24
cache: SortedDict[int, SortedDict[int, List[int]]] = {}
self.verticalTraversalImpl(cache, root, 0, 0)
result: List[List[int]] = []
for d in sorted(cache):
result.append([])
for s in sorted(cache[d]):
for v in sorted(cache[d][s]):
result[-1].append(v)
return result
# [0,2,1,3,null,null,null,4,5,null,7,6,null,10,8,11,9]
root1 = TreeNode(3)
root1.left = TreeNode(9)
root1.right = TreeNode(20)
root1.right.left = TreeNode(15)
root1.right.right = TreeNode(7)
root2 = TreeNode(1)
root2.left = TreeNode(2)
root2.left.left = TreeNode(4)
root2.left.right = TreeNode(5)
root2.right = TreeNode(3)
root2.right.left = TreeNode(6)
root2.right.right = TreeNode(7)
tests = [
(root1, [[9],[3,15],[20],[7]]),
# Memory Usage: 18.8 MB, less than 5.07% of Python3 online submissions for Convert BST to Greater Tree.
from Common.Leetcode import TreeNode
from Common.TreeUtils import printTree
class Solution:
def convertBST(self, root: TreeNode) -> TreeNode:
def convertBSTImpl(root: TreeNode, v: int) -> (TreeNode, int):
if not root:
return None, 0
newRight, sumRight = convertBSTImpl(root.right, v)
newRoot = TreeNode(root.val + sumRight + v)
newLeft, sumLeft = convertBSTImpl(root.left, newRoot.val)
newRoot.left = newLeft
newRoot.right = newRight
return newRoot, sumLeft + root.val + sumRight
return convertBSTImpl(root, 0)[0]
root1 = TreeNode(4)
root1.left = TreeNode(1)
root1.right = TreeNode(6)
root1.left.left = TreeNode(0)
root1.left.right = TreeNode(2)
root1.left.right.right = TreeNode(3)
root1.right.left = TreeNode(5)
root1.right.right = TreeNode(7)
root1.right.right.right = TreeNode(8)
printTree(Solution().convertBST(root1))
class Solution:
def binaryTreePaths(self, root: TreeNode) -> List[str]:
def binaryTreePathsImpl(root: TreeNode, result: List[str], path: str):
if root is None:
return
newpath: str = path
if len(newpath) > 0:
newpath += "->"
newpath += str(root.val)
if root.left is None and root.right is None:
result.append(newpath)
else:
if root.left is not None:
binaryTreePathsImpl(root.left, result, newpath)
if root.right is not None:
binaryTreePathsImpl(root.right, result, newpath)
result: List[str] = []
binaryTreePathsImpl(root, result, "")
return result
t1 = TreeNode(1)
t1.left = TreeNode(2)
t1.left.right = TreeNode(5)
t1.right = TreeNode(3)
tests = [(t1, ['1->2->5', '1->3'])]
run_functional_tests(Solution().binaryTreePaths, tests)
"""
Runtime: 40 ms, faster than 89.58% of Python3 online submissions for Path Sum.
Memory Usage: 15.4 MB, less than 98.89% of Python3 online submissions for Path Sum.
"""
class Solution:
def hasPathSum(self, root: TreeNode, sum: int) -> bool:
if root is None:
return False
if root.left is None and root.right is None:
return sum == root.val
if self.hasPathSum(root.left, sum - root.val):
return True
return self.hasPathSum(root.right, sum - root.val)
t1 = TreeNode(5)
t1.left = TreeNode(4)
t1.right = TreeNode(8)
t1.left.left = TreeNode(11)
t1.left.left.left = TreeNode(7)
t1.left.left.right = TreeNode(2)
t1.right.left = TreeNode(13)
t1.right.right = TreeNode(4)
t1.right.right.right = TreeNode(1)
tests = [
(t1, 22, True)
]
right_end = impl(root.right)
right = root.right
root.right = root.left
root.left = None
if left_end:
left_end.right = right
else:
root.right = right
if right_end:
return right_end
if left_end:
return left_end
return root
return impl(root)
tests = [[
TreeNode(1, TreeNode(2, TreeNode(3), TreeNode(4)),
TreeNode(5, null, TreeNode(6))),
TreeNode(
1, null,
TreeNode(
2, null,
TreeNode(3, null, TreeNode(4, null, TreeNode(5, null,
TreeNode(6))))))
], [null, null], [TreeNode(0), TreeNode(0)]]
run_functional_tests(make_inplace(Solution().flatten), tests)