Divide Array in Sets of K Consecutive Numbers
<p>Given an array of integers <code>nums</code> and a positive integer <code>k</code>, check whether it is possible to divide this array into sets of <code>k</code> consecutive numbers.</p>

<p>Return <code>true</code> <em>if it is possible</em>.<strong> </strong>Otherwise, return <code>false</code>.</p>

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

<pre>
<strong>Input:</strong> nums = [1,2,3,3,4,4,5,6], k = 4
<strong>Output:</strong> true
<strong>Explanation:</strong> Array can be divided into [1,2,3,4] and [3,4,5,6].
</pre>

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

<pre>
<strong>Input:</strong> nums = [3,2,1,2,3,4,3,4,5,9,10,11], k = 3
<strong>Output:</strong> true
<strong>Explanation:</strong> Array can be divided into [1,2,3] , [2,3,4] , [3,4,5] and [9,10,11].
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> nums = [1,2,3,4], k = 3
<strong>Output:</strong> false
<strong>Explanation:</strong> Each array should be divided in subarrays of size 3.
</pre>

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

<ul>
	<li><code>1 &lt;= k &lt;= nums.length &lt;= 10<sup>5</sup></code></li>
	<li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li>
</ul>

<p>&nbsp;</p>
<strong>Note:</strong> This question is the same as&nbsp;846:&nbsp;<a href="https://leetcode.com/problems/hand-of-straights/" target="_blank">https://leetcode.com/problems/hand-of-straights/</a>
Greedy; Array; Hash Table; Sorting
func isPossibleDivide(nums []int, k int) bool {
	if len(nums)%k != 0 {
		return false
	}
	sort.Ints(nums)
	cnt := map[int]int{}
	for _, x := range nums {
		cnt[x]++
	}
	for _, x := range nums {
		if cnt[x] > 0 {
			for y := x; y < x+k; y++ {
				if cnt[y] == 0 {
					return false
				}
				cnt[y]--
			}
		}
	}
	return true
}
