ZXAlgorithm - CAT测试

https://www.lintcode.com/cat/

Bronze

Invert Binary Tree
https://www.jiuzhang.com/solution/invert-binary-tree/#tag-highlight-lang-python

Binary Tree Path Sum
https://www.jiuzhang.com/solution/binary-tree-path-sum/

Binary Tree Paths
https://www.jiuzhang.com/solution/binary-tree-paths/#tag-highlight-lang-python

Cowherd&Weaver

Silver

Kth Largest Element
https://www.jiuzhang.com/solution/kth-largest-element/#tag-highlight-lang-python
跟下面一个思路，但是多了两层判断
Sort Integers II
https://www.jiuzhang.com/solution/sort-integers-ii/#tag-highlight-lang-python
quick sort

class Solution:
    """
    @param A: an integer array
    @return: nothing
    """
    def sortIntegers2(self, A):
        # write your code here
        self.quickSort(A, 0, len(A)-1)
        
    def quickSort(self, A, start, end):
        if start >= end:
            return
        
        left, right = start, end
        pivot = A[(start+end)//2]
        
        while left <= right:
            while left <= right and A[left] < pivot:
                left += 1
            while left <= right and A[right] > pivot:
                right -= 1
            
            if left <= right:
                A[left], A[right] = A[right], A[left]
                left += 1
                right -= 1
            
        self.quickSort(A, start, right)
        self.quickSort(A, left, end)

因为while loop condition是 left <= right，loop 结束了之后肯定是 right < left。所以左边是A[start:right] 右边是A[left:end]
merge sort 再说
Sort Colors II
https://www.jiuzhang.com/solution/sort-colors-ii/#tag-highlight-lang-python
Interval-minimum-coverage
https://www.jiuzhang.com/solution/interval-minimum-coverage/#tag-other-lang-python