Easy
Given an integer numRows, return the first numRows of Pascal's triangle.
In Pascal's triangle, each number is the sum of the two numbers directly above it as shown:
Example 1:
Input: numRows = 5 Output: [[1],[1,1],[1,2,1],[1,3,3,1],[1,4,6,4,1]]
Example 2:
Input: numRows = 1 Output: [[1]]
Constraints:
1 <= numRows <= 30
class Solution:
def generate(self, numRows: int) -> List[List[int]]:
pascal = [[1]*(i+1) for i in range(numRows)]
for i in range(numRows):
for j in range(1, i):
pascal[i][j] = pascal[i-1][j-1]+ pascal[i-1][j]
return pascal