Degree of an Array

Given a non-empty array of non-negative integers nums, the degree of this array is defined as the maximum frequency of any one of its elements.

Return the smallest possible length of a (contiguous) subarray of nums, that has the same degree as nums.

Input Format:

First parameter: N

Second parameter: an array nums of size N.

Output Format:

Return the number.

Example 1:

Input: 
5
1 2 2 3 1
Output: 
2
Explanation: 
The input array has a degree of 2 because both elements 1 and 2 appear twice.
Of the subarrays that have the same degree:
[1, 2, 2, 3, 1], [1, 2, 2, 3], [2, 2, 3, 1], [1, 2, 2], [2, 2, 3], [2, 2]
The shortest length is 2. So return 2.

Example 2:

Input:
7
1 2 2 3 1 4 2
Output:
6
Explanation: 
The degree is 3 because the element 2 is repeated 3 times.
So [2,2,3,1,4,2] is the shortest subarray, therefore returning 6.

Constraints:

• 1 <= nums.length <= 5*10⁴.
• 0 <= nums[i] <= 5*10⁴-1.
• Time Complexity: O(N)
• Space Complexity: O(N)