1619. Mean of Array After Removing Some Elements

#### QUESTION:

Given an integer array arr, return the mean of the remaining integers after removing the smallest 5% and the largest 5% of the elements.

Example 1:

``````Input: arr = [1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,3]
Output: 2.00000
Explanation: After erasing the minimum and the maximum values of this array, all elements are equal to 2, so the mean is 2.
``````

Example 2:

``````Input: arr = [6,2,7,5,1,2,0,3,10,2,5,0,5,5,0,8,7,6,8,0]
Output: 4.00000
``````

Example 3:

``````Input: arr = [6,0,7,0,7,5,7,8,3,4,0,7,8,1,6,8,1,1,2,4,8,1,9,5,4,3,8,5,10,8,6,6,1,0,6,10,8,2,3,4]
Output: 4.77778
``````

Constraints:

``````20 <= arr.length <= 1000
arr.length is a multiple of 20.
0 <= arr[i] <= 105
``````

#### SOLUTION:

``````class Solution {
func trimMean(_ arr: [Int]) -> Double {
var tmpArr:[Int] = arr.sorted()
var removeCount:Int = Int(Double(tmpArr.count) * 0.05)
var sum:Int = 0
for index in removeCount...tmpArr.count - removeCount - 1 {
sum += tmpArr[index]
}
return Double(sum)/Double((tmpArr.count - removeCount * 2))
}
}
``````