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
+