Given an integer numRows, return the first numRows rows of Pascal's triangle.
Each row starts and ends with 1, and every other number is the sum of the two numbers directly above it.
Examples
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