/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
 
    public static int[] findTwoSum(int[] nums, int target) {
        HashMap<Integer, Integer> map = new HashMap<>();
 
        for (int i = 0; i < nums.length; i++) {
            int complement = target - nums[i];
 
            if (map.containsKey(complement)) {
                return new int[] { map.get(complement), i };
            }
 
            map.put(nums[i], i);
        }
 
        return new int[] {}; // No solution found
    }
 
    public static void main(String[] args) {
        int[] nums = {2, 7, 11, 15};
        int target = 9;
 
        int[] result = findTwoSum(nums, target);
        if (result.length == 2) {
            System.out.println("Indices: " + result[0] + ", " + result[1]);
        } else {
            System.out.println("No solution found.");
        }
    }
}
 
 

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