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Algorithms & data structures

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Algorithms & data structures easy

Count Smaller Elements to the Right in Python

Return a list where each index counts how many elements to its right are smaller than that element using a clean O(n²) nested-loop approach.

brute-force nested-loops counting
Python 
def count_smaller_elements(arr):
    """
    Return a list where result[i] is the number of elements 
    to the right of arr[i] that are smaller than arr[i].
    """
    result = []
    for i in range(len(arr)):
        count = 0
        for j in range(i + 1, len(arr)):
            if arr[j] < arr[i]:
               …
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