Given a stream of incoming numbers, find average or mean of the stream at every point.

Example 1:
Input:
n = 5
arr[] = {10, 20, 30, 40, 50}
Output: 10.00 15.00 20.00 25.00 30.00
Explanation:
10 / 1 = 10.00
(10 + 20) / 2 = 15.00
(10 + 20 + 30) / 3 = 20.00
And so on.

Example 2:
Input:
n = 2
arr[] = {12, 2}
Output: 12.00 7.00
Explanation:
12 / 1 = 12.00
(12 + 2) / 2 = 7.00

Your Task:
You don't need to read input or print anything. Your task is to complete the function streamAvg() which takes the array of integers arr and n as input parameters and returns an array of type float denoting the average at every point in the stream.

Expected Time Complexity: O(n)
Expected Auxiliary Space: O(1)

Constraints:
1 ≤ n ≤ 10^{5}
1 ≤ arr[i] ≤ 10^{6}

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