public int[] twoSum(int[] nums, int target) {

        Map<Integer,Integer> map = new HashMap<>();

        for(int i =0; i< nums.length; i++) {

            if(map.containsKey(target - nums[i])){

                return new int[]{map.get(target - nums[i]), i};

            }else {

                map.put(nums[i], i);

            }

        }

        return new int[]{-1,-1};

    }

​

****************2 nd way *************************

​

public int[] twoSum(int[] nums, int target) {

        int arr[] = new int[2];

        for (int i = 0; i < nums.length; i++) {

            for (int j = 0; j < nums.length; j++) {

                if (i != j)

                    if (nums[i] + nums[j] == target) {

                        arr[0] = i;

                        arr[1] = j;

                        break;

                    }

            }

        }

        return arr;

    }

class Solution {

    public int[] twoSum(int[] nums, int target) {

        int arr[]= new int[2];

        for(int i =0; i<nums.length; i++){

            for(int j= i+1; j< nums.length; j++){

            if(nums[i]+ nums[j]== target){

            arr[0]= i;

            arr[1] = j;

            }

            }

        }

        return arr;

    }

}