DSA_sheets/dsa/src/main/java/com/hithomelabs/dsa/array/two_sum/HashMapSolution.java

package com.hithomelabs.dsa.array.two_sum;
import java.util.Map;

public class HashMapSolution implements Solvable {

    @Override
    public int[] solve(int[] nums, int target) {
        // Create a map to store the numbers and their corresponding indices
        Map<Integer, Integer> map = new HashMap();
        
        // Iterate through the array of numbers
        for (int i = 0; i < nums.length; i++){
            // Check if the complement (target - current number) exists in the map
            if (map.containsKey(target - nums[i])){
                // If found, return the indices of the current number and its complement
                int[] solution = {i, map.get(target - nums[i])};
                return solution;
            }
            else
                // If not found, add the current number and its index to the map
                map.put(nums[i], i);
        }
        // Return null if no solution is found
        return null;     
    }
}