Two Sum solution using TypeScript

leetcode

Below is my TypeScript solution to the LeetCode "Two Sum" question using a Hash Map to find the compliment.

Because each element in the array will be visited one time, the time complexity is O(n), where n represents the number of elements in the array.

This approach will place n elements in the map in the worst case, making the space complexity O(n).

/**
 * Given an array of integers, return indices of the two numbers 
 * such that they add up to a specific target.
 *
 *   Time Complexity: O(n)
 *   Space Complexity: O(n)
 *
 *   Input:  nums = [2, 7, 11, 15], target = 9
 *   Output: [0, 1]
 *   Because nums[0] + nums[1] = 2 + 7 = 9
 */
function twoSum(nums: number[], target: number): number[] {
    const map: Map<number, number> = new Map();
    let result: number[] = [];
    
    for (let i = 0; i < nums.length; i++) {
        const current = nums[i];
        const match = map.get(target - current);

        if (match !== undefined) {
            result = [i, match];
            break;
        }
        map.set(current, i); 
    }

    return result;
}

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