import java.util.HashMap;

import java.util.Map;

public class Geegong {

/**

* time complexity : O(n)

* space complexity : O(n)

* @param nums

* @param target

* @return int[]

*/

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

int[] result = new int[2];

// key : value, value = index

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

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

int findOne = target - nums[index];

if (maps.containsKey(findOne)) {

result[0] = maps.get(findOne);

result[1] = index;

return result;

}

maps.put(nums[index], index);

}

return result;

}

}