Software Engineer

First I came up with a naive approach to use bubble sort or quick sort. He advised me to not use any algorithm. So, after thinking a little I came up with the approach of two pointers. I told about my approach to the interviewer He nodded and yes told me to implement the same.

function segregateZerosAndOnes(arr):
Step 1: Initialize pointers
left = 0
right = length(arr) - 1

Step 2: Traverse the array
while left <= right:
Step 3: Move the left pointer to find the first '1' from the left
while arr[left] == 0:
left++

Step 4: Move the right pointer to find the first '0' from the right
while arr[right] == 1:
right--

Step 5: Swap elements if necessary
if left <= right:
swap(arr[left], arr[right])
left++
right--
Step 6: The array is now segregated with '0's on the left and '1's on the right.

Step 7: After that, I was able to implement it. Interviewer was happy