CA 09 - Move All Negative Elements to end

Problem Statement: here

PS Understanding:
An input array with a mix of positive and negative numbers are given. The task is to move all the negative numbers to the end of the array without changing the order of positive elements. The trick is to do this arrangement in-place and not use any temporary array.

Solution:

arr = [1, -1, 3, 2, -7, -5, 11, 6]
n = len(arr)
i = 0
while i < n:
    if arr[i] < 0:
        temp = arr[i]
        for j in range(i, n - 1):
            arr[j] = arr[j + 1]
        arr[n - 1] = temp
        n -= 1
    else:
        i += 1
print(arr)

• Initialize the values n= length of the array, i= first element of array.
• If the element at arr[i] is negative, store it in a temporary variable, then move it to the end of the array. Decrease the value of n, since value at position n is already a negative number.
• Else if the element at arr[i] is positive, move to the next element.