public class Solution
extends Object
119 - Pascal's Triangle II\.
Easy
Given an integer `rowIndex`, return the `rowIndexth` ( **0-indexed** ) row of the **Pascal's triangle**.
In **Pascal's triangle** , each number is the sum of the two numbers directly above it as shown:
**Example 1:**
**Input:** rowIndex = 3
**Output:** [1,3,3,1]
**Example 2:**
**Input:** rowIndex = 0
**Output:** [1]
**Example 3:**
**Input:** rowIndex = 1
**Output:** [1,1]
**Constraints:**
* `0 <= rowIndex <= 33`
**Follow up:** Could you optimize your algorithm to use only `O(rowIndex)` extra space?