LeetCode_Pascal's Triangle

Posted on | In | Views:

Pascal’s Triangle

Given a non-negative integer numRows, generate the first numRows of Pascal’s triangle.
(杨辉三角)

Example:



1. 逐层生成

根据杨辉三角的规律，组成生成杨辉三角，具体实现过程如下：

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
class Solution:
    def generate(self, numRows: int) -> List[List[int]]:
        if numRows == 0:
            return []
        
        results = []
        for i in range(numRows):
            if i == 0:
                results.append([1])
            else:
                list = [1]
                for j in range(i-1):
                    list.append(results[i-1][j] + results[i-1][j+1])
                list.append(1)
                results.append(list)
            
        return results