Bubblesort runtime is n^2 for average and worst case scenario. Memory usage is constant.

bubbleSort.swift

func bubbleSort(nums: inout [Int]) -> [Int] {
    
    while true {
        var swapped = false
        
        for i in 0..<nums.count - 1 {
            if nums[i] > nums[i + 1] {
                let temp = nums[i]
                nums[i] = nums[i + 1]
                nums[i + 1] = temp
                swapped = true
            }
        }
        
        if !swapped {
        	return nums
        }
    }
}

bubbleSort(nums: &randomNumbers)