leetcode-problemset/leetcode-cn/problem (English)/左右元素和的差值(English) [left-and-right-sum-differences].html

<p>Given a <strong>0-indexed</strong> integer array <code>nums</code>, find a <strong>0-indexed </strong>integer array <code>answer</code> where:</p>

<ul>
    <li><code>answer.length == nums.length</code>.</li>
    <li><code>answer[i] = |leftSum[i] - rightSum[i]|</code>.</li>
</ul>

<p>Where:</p>

<ul>
    <li><code>leftSum[i]</code> is the sum of elements to the left of the index <code>i</code> in the array <code>nums</code>. If there is no such element, <code>leftSum[i] = 0</code>.</li>
    <li><code>rightSum[i]</code> is the sum of elements to the right of the index <code>i</code> in the array <code>nums</code>. If there is no such element, <code>rightSum[i] = 0</code>.</li>
</ul>

<p>Return <em>the array</em> <code>answer</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> nums = [10,4,8,3]
<strong>Output:</strong> [15,1,11,22]
<strong>Explanation:</strong> The array leftSum is [0,10,14,22] and the array rightSum is [15,11,3,0].
The array answer is [|0 - 15|,|10 - 11|,|14 - 3|,|22 - 0|] = [15,1,11,22].
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> nums = [1]
<strong>Output:</strong> [0]
<strong>Explanation:</strong> The array leftSum is [0] and the array rightSum is [0].
The array answer is [|0 - 0|] = [0].
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= nums.length &lt;= 1000</code></li>
	<li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li>
</ul>