Given an array. Calculate the sum of lengths of contiguous subarrays having all distinct elements.

Example 1:
Input:
N=3
arr[] = { 1,2,3 }
Output: 10
Explanation:
{1, 2, 3} is a subarray of length 3 with
distinct elements. Total length of length
three = 3. {1, 2}, {2, 3} are 2 subarray
of length 2 with distinct elements. Total
length of lengths two = 2 + 2 = 4
{1}, {2}, {3} are 3 subarrays of length 1
with distinct element. Total lengths of
length one = 1 + 1 + 1 = 3
Sum of lengths = 3 + 4 + 3 = 10
Example 2:
Input:
N=1
arr[] = { 1 }
Output: 1
Explanation:
{1} is the only subarray with distinct
elements of length 1.
Your Task:
You don't need to read input or print anything. Your task is to complete the function sumoflength() that takes array arr and integer N as input parameters and returns the sum of lengths of contiguous subarrays having all distinct elements.
Expected Time Complexity: O(N).
Expected Auxiliary Space: O(N).

Constraints:
1 ≤ N ≤ 10^{6}

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