LeetCode Pascal's Triangle && Pascal's Triangle II Python

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Pascal's Triangle
　　Given numRows, generate the first numRows of Pascal's triangle.
　　For example, given numRows = 5,
Return

[
[1],
[1,1],
[1,2,1],
[1,3,3,1],
[1,4,6,4,1]
]


class Solution:
# @return a list of lists of integers

def generate(self, numRows):
def g(ls):
res = [1]
left = 1
for i in range(1,len(ls)):
res.append(left+ls)
left = ls
res.append(1)
return res
res = []
if numRows < 3:
if numRows == 0:
return res
for i in range(1,numRows+1):
res.append([1]*i)
else:
res.append([1])
res.append([1,1])
for i in range(2,numRows):
res.append(g(res[i-1]))
return res

　　


　　

Pascal's Triangle II
　　Given an index k, return the kth row of the Pascal's triangle.
　　For example, given k = 3,
Return [1,3,3,1].
　　Note:
Could you optimize your algorithm to use only O(k) extra space?
　　



class Solution:
# @return a list of integers
def getRow(self, rowIndex):
def g(ls):
res = [1]
left = 1
for i in range(1,len(ls)):
res.append(left+ls)
left = ls
res.append(1)
return res
res = []
if rowIndex< 2:
res = [1]*(rowIndex+1)
else:
res.append([1,1])
for i in range(rowIndex):
res = (g(res))
return res