In-Place Sort for Two Colors | Dataford Interview Questions

An eToro watchlist component stores market-status markers in an array. Each marker is encoded as 0 for green and 1 for red. Rearrange the array in place so that all green markers appear before all red markers.

Implement a function that modifies the input list directly and returns the same list. Do not use Python's built-in sorting function or allocate another array.

Formal Specification

Given a list colors containing only integers 0 and 1, reorder it so every 0 appears before every 1. The relative order among equal values does not matter. Return the modified list.

Constraints

0 <= len(colors) <= 10^5
Every element is either 0 or 1
The input list must be modified in place
Use O(1) auxiliary space

Function Signature

def sort_two_colors(colors):

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