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$ curl repovive.com/roadmaps/fundamental-algorithms/bit-manipulation/single-number-implementation

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$ curl repovive.com/roadmaps/fundamental-algorithms/bit-manipulation/single-number-implementation

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Single Number - Implementation - Bit Manipulation | Fundamental Algorithms | Repovive

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Fundamental Algorithms8 sections · 294 units2h total

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Single Number - Implementation

Here is the implementation:

function singleNumber(nums):
    result = 0
    for num in nums:
        result = result XOR num
    return result

This runs in $O(n)$ time with $O(1)$ space (excluding input). XOR is associative and commutative, so order doesn't matter.