LeetCode – Arrays – Create Target Array in the Given Order

Given two arrays of integers nums and index. Your task is to create target array under the following rules:

• Initially target array is empty.
• From left to right read nums[i] and index[i], insert at index index[i] the value nums[i] in target array.
• Repeat the previous step until there are no elements to read in nums and index.

Return the target array.

It is guaranteed that the insertion operations will be valid.

Example 1:

Input: nums = [0,1,2,3,4], index = [0,1,2,2,1]
Output: [0,4,1,3,2]
Explanation:
nums       index     target
0            0        [0]
1            1        [0,1]
2            2        [0,1,2]
3            2        [0,1,3,2]
4            1        [0,4,1,3,2]

Java Solution:

class Solution {
    public int[] createTargetArray(int[] nums, int[] index) {
        List<Integer> targetList = new ArrayList<Integer>();
        for(int i=0;i<nums.length;i++){
            targetList.add(index[i], nums[i]);
        }
        int[] arr = targetList.stream().mapToInt(Integer::intValue).toArray();        
        return arr;
    }
}