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Algorithms & data structures

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Algorithms & data structures easy

Find the Equilibrium Index of a List in Python

Find every index in a list where the sum of elements to its left equals the sum to its right, using a single pass.

equilibrium-index prefix-sums arrays
Python 
def find_equilibrium_indexes(arr):
    total = sum(arr)
    left_sum = 0
    indexes = []
    for i, num in enumerate(arr):
        total -= num
        if left_sum == total:
            indexes.append(i)
        left_sum += num
    return indexes

if __name__ == "__main__":
    test = [1, 2, 3, -1, 2, 3]
    result =…
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