class Solution {
public int[] twoSum(int[] nums, int target) {
int[] result = new int[2];
if(nums.length == 0) return result;
HashMap<Integer, Integer> record = new HashMap<>();
for(int i = 0; i < nums.length; i ++){
record.put(nums[i], i);
}
for(int i = 0; i < nums.length; i ++){
if(record.containsKey(target - nums[i]) && record.get(target - nums[i]) != i){
result[0] = i;
result[1] = record.get(target - nums[i]);
}
}
return result;
}
}