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?
Solution:
This one is easy. If we modify the previous array instead of creating a new array, we only need O(k) extra space.
The following code passes the LeetCode Online Large Judge.

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