Find two sum

TwoSum.java

package problem;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class TwoSum {
  public static void main(String[] args) {
    List<int[]> array = new TwoSum().twoSum(new int[]{3, 4, 5, 6}, 5);
    for (int[] arr : array) {
      System.out.println(Arrays.toString(arr));
    }
  }

  public List<int[]> twoSum(int[] nums, int target) {
    for (int i = 0; i < nums.length; i++) {
      nums[i] *= nums[i];
    }
    target *= target;

    List<int[]> result = new ArrayList<>();
    Map<Integer, Integer> m = new HashMap<>();
    for (int i = 0; i < nums.length; i++) {
      if (m.containsKey(nums[i])) {
        int[] pair = new int[2];
        pair[0] = m.get(nums[i]) + 1;
        pair[1] = i + 1;
        result.add(pair);
      } else {
        m.put(target - nums[i], i);
      }
    }
    return result;
  }
}

Input

new int[]{3, 4, 5, 6}, 5

Output

[1, 2]

so the output will be [1, 2] because it shows index + 1 of 3 and index + 1 of 4.