phongngtuan

class Solution:
    def pruneTree(self, root: TreeNode) -> TreeNode:
        if root == None:
            return None
        left = self.pruneTree(root.left)
        right = self.pruneTree(root.right)
        if root.val == 1 or left or right: # not prunable
            root = TreeNode(root.val)
            root.left = left
            root.right = right

phongngtuan

import heapq

class Solution:
    def twoCitySchedCost(self, costs: List[List[int]]) -> int:
        heap = []
        for cost in costs:
            heapq.heappush(heap, (-abs(cost[0] - cost[1]), cost[0], cost[1]))

        N = len(costs) / 2
        total = 0

phongngtuan

class Solution:
    def generateMatrix(self, n: int) -> List[List[int]]:
        if n == 1:
            return [[1]]
        mat = [[0 for i in range(n)] for j in range(n)]
        counter = 1
        for i in range(0, n):
            x, y = i, i
            width = n - i * 2
            height = width - 2

phongngtuan

class TrieNode:
    def __init__(self, c: str, path: str):
        self.c = c  # type: str
        self.counter = 0  # type: str
        self.path = path  # type: str
        self.children = dict()  # type: Dict[str, TrieNode]

    def add(self, key: str, path: str):
        if len(key) == 0:
            self.counter += 1