#1 Two Sum Array Problem LeetCode Solve With HashMap Java| Solve Problem Java Leetcode #2023 #tech

@softwaretechit

LeetCode Problems Solve Using Java | LeetCode Solution | Java Leetcode Solution #leetcode #java #coding #leetcodequestions

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.

Visit For More :-https://softwaretechit.com

HackerRank Problems Solution :-https://softwaretechit.com/category/hackerrank

Blog:- https://blog.softwaretechit.com

Shop:- https://shop.softwaretechit.com

Important Link’s :-https://home.softwaretechit.com

Projects :- https://link.softwaretechit.com

1. Two Sum

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.

Example 1:

Input: nums = [2,7,11,15], target = 9

Output: [0,1]

Explanation: Because nums[0] + nums[1] == 9, we return [0, 1].

Example 2:

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

Output: [1,2]

Example 3:

Input: nums = [3,3], target = 6

Output: [0,1]

Constraints:

2 <= nums.length <= 104

-109 <= nums[i] <= 109

-109 <= target <= 109

Only one valid answer exists.

Follow-up: Can you come up with an algorithm that is less than O(n2) time complexity?

Solution :-

class Solution {
    public int[] twoSum(int[] nums, int target) {
        int n=nums.length;
        Map<Integer,Integer> map=new HashMap<>();
        int[] result=new int[2];
        for(int i=0;i<n;i++){
            if(map.containsKey(target-nums[i])){
                result[1]=i;
                result[0]=map.get(target-nums[i]);
                return result;
            }
            map.put(nums[i],i);
        }
        return result;
    }
}