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Algorithms

You are given a sorted unique integer array <code>nums</code>.

A range <code>[a,b]</code> is the set of all integers from <code>a</code> to <code>b</code> (inclusive).

Return the smallest sorted list of ranges that cover all the numbers in the array exactly. That is, each element of <code>nums</code> is covered by exactly one of the ranges, and there is no integer <code>x</code> such that <code>x</code> is in one of the ranges but not in <code>nums</code>.

Each range <code>[a,b]</code> in the list should be output as:

<ul>
	<li><code>&quot;a-&gt;b&quot;</code> if <code>a != b</code></li>
	<li><code>&quot;a&quot;</code> if <code>a == b</code></li>
</ul>

&nbsp;
Example 1:

<pre>
Input: nums = [0,1,2,4,5,7]
Output: [&quot;0-&gt;2&quot;,&quot;4-&gt;5&quot;,&quot;7&quot;]
Explanation: The ranges are:
[0,2] --&gt; &quot;0-&gt;2&quot;
[4,5] --&gt; &quot;4-&gt;5&quot;
[7,7] --&gt; &quot;7&quot;
</pre>

Example 2:

<pre>
Input: nums = [0,2,3,4,6,8,9]
Output: [&quot;0&quot;,&quot;2-&gt;4&quot;,&quot;6&quot;,&quot;8-&gt;9&quot;]
Explanation: The ranges are:
[0,0] --&gt; &quot;0&quot;
[2,4] --&gt; &quot;2-&gt;4&quot;
[6,6] --&gt; &quot;6&quot;
[8,9] --&gt; &quot;8-&gt;9&quot;
</pre>

&nbsp;
Constraints:

<ul>
	<li><code>0 &lt;= nums.length &lt;= 20</code></li>
	<li><code>-231 &lt;= nums[i] &lt;= 231 - 1</code></li>
	<li>All the values of <code>nums</code> are unique.</li>
	<li><code>nums</code> is sorted in ascending order.</li>
</ul>