<p>Given an array of integers <code>nums</code> and an integer <code>k</code>. A continuous subarray is called <strong>nice</strong> if there are <code>k</code> odd numbers on it.</p>



<p>Return <em>the number of <strong>nice</strong> sub-arrays</em>.</p>



<p>&nbsp;</p>

<p><strong>Example 1:</strong></p>



<pre>

<strong>Input:</strong> nums = [1,1,2,1,1], k = 3

<strong>Output:</strong> 2

<strong>Explanation:</strong> The only sub-arrays with 3 odd numbers are [1,1,2,1] and [1,2,1,1].

</pre>



<p><strong>Example 2:</strong></p>



<pre>

<strong>Input:</strong> nums = [2,4,6], k = 1

<strong>Output:</strong> 0

<strong>Explanation:</strong> There is no odd numbers in the array.

</pre>



<p><strong>Example 3:</strong></p>



<pre>

<strong>Input:</strong> nums = [2,2,2,1,2,2,1,2,2,2], k = 2

<strong>Output:</strong> 16

</pre>



<p>&nbsp;</p>

<p><strong>Constraints:</strong></p>



<ul>

	<li><code>1 &lt;= nums.length &lt;= 50000</code></li>

	<li><code>1 &lt;= nums[i] &lt;= 10^5</code></li>

	<li><code>1 &lt;= k &lt;= nums.length</code></li>

</ul>