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Two Sum (JavaScript)


Today we solve a very popular 'problem' on Leetcode #1 Two Sum

Difficulty level: Easy

Related Topics: Hash Table, Array

Disclaimer: You might have different results in Runtime and Memory Usage, it's okay 🤣 it how it works.


Description:

Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.

You may assume that each input would have exactly one solution, and you may not use the same element twice.

You can return the answer in any order.

Examples:

Input: nums = [2,7,11,15], target = 9
Output: [0,1]
Output: Because nums[0] + nums[1] == 9, we return [0, 1].


Input: nums = [3,2,4], target = 6
Output: [1,2]


Input: nums = [3,3], target = 6
Output: [0,1]

Constraints:

2 <= nums.length <= 105
-109 <= nums[i] <= 109
-109 <= target <= 109
Only one valid answer exists.

Solution 1

var twoSum = function(nums, target) {

    for(let i = 0; i < nums.length; i++) {
        for(let j = i + 1; j < nums.length; j++) {
            if(nums[i] + nums[j] === target) return [i,j]
        }
    }

    return [0,0]
};

Let's submit it and see the result.

Runtime: 132 ms, faster than 37.12% of JavaScript online submissions for Two Sum.
Memory Usage: 36.8 MB, less than 90.78% of JavaScript online submissions for Two Sum.
© 2021, Andrew Losseff