Problems and solution

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.

Input: nums = [2,7,11,15], target = 9 Output: [0,1]

class Solution {
    public int[] twoSum(int[] nums, int target) {
        Map<Integer,Integer> numMap =  new HashMap<>();

        for(int i = 0 ; i < nums.length;i++ ){
           int complement = target-nums[i];
           if(numMap.containsKey(complement)){
            return new int[]{numMap.get(complement),i};
           }
           numMap.put(nums[i],i);

        }
        return null;

    }
}