Pascal's Triangle
<p>Given an integer <code>numRows</code>, return the first numRows of <strong>Pascal&#39;s triangle</strong>.</p>

<p>In <strong>Pascal&#39;s triangle</strong>, each number is the sum of the two numbers directly above it as shown:</p>
<img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/0100-0199/0118.Pascal%27s%20Triangle/images/PascalTriangleAnimated2.gif" style="height:240px; width:260px" />
<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> numRows = 5
<strong>Output:</strong> [[1],[1,1],[1,2,1],[1,3,3,1],[1,4,6,4,1]]
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> numRows = 1
<strong>Output:</strong> [[1]]
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= numRows &lt;= 30</code></li>
</ul>
Array; Dynamic Programming
class Solution:
    def generate(self, numRows: int) -> List[List[int]]:
        f = [[1]]
        for i in range(numRows - 1):
            g = [1] + [a + b for a, b in pairwise(f[-1])] + [1]
            f.append(g)
        return f
