Project Notes

Pascal's Triangle II

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Description

tab: English
 
<p>Given an integer <code>rowIndex</code>, return the <code>rowIndex<sup>th</sup></code> (<strong>0-indexed</strong>) row of the <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://upload.wikimedia.org/wikipedia/commons/0/0d/PascalTriangleAnimated2.gif" style="height:240px; width:260px" />
<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> rowIndex = 3
<strong>Output:</strong> [1,3,3,1]
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> rowIndex = 0
<strong>Output:</strong> [1]
</pre><p><strong class="example">Example 3:</strong></p>
<pre><strong>Input:</strong> rowIndex = 1
<strong>Output:</strong> [1,1]
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>
 
<ul>
	<li><code>0 &lt;= rowIndex &lt;= 33</code></li>
</ul>
 
<p>&nbsp;</p>
<p><strong>Follow up:</strong> Could you optimize your algorithm to use only <code>O(rowIndex)</code> extra space?</p>
 
 
 
---
 
[submissions](https://leetcode.com/problems/pascals-triangle-ii/submissions/) | [solutions](https://leetcode.com/problems/pascals-triangle-ii/solutions/)
 
 
tab: 中文
 
<p>给定一个非负索引 <code>rowIndex</code>，返回「杨辉三角」的第 <code>rowIndex</code><em> </em>行。</p>
 
<p><small>在「杨辉三角」中，每个数是它左上方和右上方的数的和。</small></p>
 
<p><img alt="" src="https://pic.leetcode-cn.com/1626927345-DZmfxB-PascalTriangleAnimated2.gif" /></p>
 
<p> </p>
 
<p><strong>示例 1:</strong></p>
 
<pre>
<strong>输入:</strong> rowIndex = 3
<strong>输出:</strong> [1,3,3,1]
</pre>
 
<p><strong>示例 2:</strong></p>
 
<pre>
<strong>输入:</strong> rowIndex = 0
<strong>输出:</strong> [1]
</pre>
 
<p><strong>示例 3:</strong></p>
 
<pre>
<strong>输入:</strong> rowIndex = 1
<strong>输出:</strong> [1,1]
</pre>
 
<p> </p>
 
<p><strong>提示:</strong></p>
 
<ul>
	<li><code>0 <= rowIndex <= 33</code></li>
</ul>
 
<p> </p>
 
<p><strong>进阶：</strong></p>
 
<p>你可以优化你的算法到 <code><em>O</em>(<i>rowIndex</i>)</code> 空间复杂度吗？</p>
 
 
 
---
 
[提交记录](https://leetcode.cn/problems/pascals-triangle-ii/submissions/) | [题解](https://leetcode.cn/problems/pascals-triangle-ii/solution/)

Solutions & Notes

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