描述
Given an index k, return the kth row of the Pascal’s triangle.
For example, given k = 3,
Return [1,3,3,1].
分析
Pascal Triangle的后续。用类似动态规划的降维方式，可以实现空间O(n)的算法。
代码
Python
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| class Solution(object):
def getRow(self, rowIndex):
"""
:type rowIndex: int
:rtype: List[int]
"""
rs = [0] * (rowIndex + 1)
rs[0] = 1
for i in xrange(1, rowIndex + 1):
rs[i] = 1
for j in xrange(i - 1, 0, -1):
rs[j] += rs[j - 1]
return rs
|