#3 Easy O(n) O(n) Animated

Two Sum

Given an array of integers and a target, return indices of two numbers that add up to target.

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Approach: Hash Map — One Pass

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Description

Given an array of integers and a target, return indices of two numbers that add up to target.

Constraints

Time Complexity: O(n)
Space Complexity: O(n)

Solution — Hash Map — One Pass

O(n) O(n)

def twoSum(nums, target):
    seen = {}                    # line 1
    for i, num in enumerate(nums):  # line 2
        complement = target - num   # line 3
        if complement in seen:      # line 4
            return [seen[complement], i]  # line 5
        seen[num] = i              # line 6
    return []                      # line 7

Valid Anagram

Group Anagrams

Two Sum

Steps

Description

Constraints

Tags

Solution — Hash Map — One Pass