Python实现"杨辉三角||"的两种方法

给定一个非负整数k(k<=33),返回杨辉三角的第k行

注意:返回行从0开始

在杨辉三角中,每个数是它左上方和右上方的数的和 

Example:

Input: 3
Output: [1,3,3,1]

进阶:你可以优化你的算法到O(k)的空间复杂度么?

1:zip()加sum()的方法

def getRow(self, rowIndex):
        """
        :type rowIndex: int
        :rtype: List[int]
        """
        curLevelList = [1]
        n = 0
        while n<rowIndex:
            curLevelList = [sum(t) for t in zip([0]+curLevelList, curLevelList+[0])]
            n += 1
        return curLevelList

2:map()方法

def getRow(self, rowIndex):
        """
        :type rowIndex: int
        :rtype: List[int]
        """
        curLevelList = [1]
        n = 0
        while n<rowIndex:
            curLevelList = map(lambda x,y:x+y, [0]+curLevelList, curLevelList+[0])
            n += 1
        return curLevelList

算法题来自:https://leetcode-cn.com/problems/pascals-triangle-ii/description/

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转载自blog.csdn.net/qiubingcsdn/article/details/82466447
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