Two Sum

Find indices of two numbers in an array that add up to a target value using a hash map for O(n) time complexity.

Code

Algorithms

seen = {}
result = None
for i, num in enumerate(arr):
    complement = target - num
    if complement in seen:
        result = [seen[complement], i]
        break
    seen[num] = i
result

Parameters

arr(array)

Array of numbers

target(number)

Target sum

Server

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