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307-range-sum-query-mutable/README.md

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+<h2><a href="https://leetcode.com/problems/range-sum-query-mutable/">307. Range Sum Query - Mutable</a></h2><h3>Medium</h3><hr><div><p>Given an integer array <code>nums</code>, handle multiple queries of the following types:</p>
+
+<ol>
+	<li><strong>Update</strong> the value of an element in <code>nums</code>.</li>
+	<li>Calculate the <strong>sum</strong> of the elements of <code>nums</code> between indices <code>left</code> and <code>right</code> <strong>inclusive</strong> where <code>left &lt;= right</code>.</li>
+</ol>
+
+<p>Implement the <code>NumArray</code> class:</p>
+
+<ul>
+	<li><code>NumArray(int[] nums)</code> Initializes the object with the integer array <code>nums</code>.</li>
+	<li><code>void update(int index, int val)</code> <strong>Updates</strong> the value of <code>nums[index]</code> to be <code>val</code>.</li>
+	<li><code>int sumRange(int left, int right)</code> Returns the <strong>sum</strong> of the elements of <code>nums</code> between indices <code>left</code> and <code>right</code> <strong>inclusive</strong> (i.e. <code>nums[left] + nums[left + 1] + ... + nums[right]</code>).</li>
+</ul>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+
+<pre><strong>Input</strong>
+["NumArray", "sumRange", "update", "sumRange"]
+[[[1, 3, 5]], [0, 2], [1, 2], [0, 2]]
+<strong>Output</strong>
+[null, 9, null, 8]
+
+<strong>Explanation</strong>
+NumArray numArray = new NumArray([1, 3, 5]);
+numArray.sumRange(0, 2); // return 1 + 3 + 5 = 9
+numArray.update(1, 2);   // nums = [1, 2, 5]
+numArray.sumRange(0, 2); // return 1 + 2 + 5 = 8
+</pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>1 &lt;= nums.length &lt;= 3 * 10<sup>4</sup></code></li>
+	<li><code>-100 &lt;= nums[i] &lt;= 100</code></li>
+	<li><code>0 &lt;= index &lt; nums.length</code></li>
+	<li><code>-100 &lt;= val &lt;= 100</code></li>
+	<li><code>0 &lt;= left &lt;= right &lt; nums.length</code></li>
+	<li>At most <code>3 * 10<sup>4</sup></code> calls will be made to <code>update</code> and <code>sumRange</code>.</li>
+</ul>
+</div>