# [Solved] 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:

## Question

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?

## Python Solution

```class Solution:
def getRow(self, n: int) -> List[int]:
res = [[1],[1,1],[1,2,1]]
if n<3:
return(res[n])
else:
n=n+1
for i in range(3,n):
a=[1]
if i%2==0:
for j in range(i//2):
a.append(res[-1][j] + res[-1][j+1])
re = a+a[::-1][1:]
else:
for j in range((i//2)+1):
a.append(res[-1][j] + res[-1][j+1])
re = a+a[::-1][2:]
res.append(re)
return res[-1]```