Leetcode 1441. Build an Array With Stack Operations

class Solution {
    public List<String> buildArray(int[] target, int n) {
        ArrayList<String> result = new ArrayList<>();
        
        int index = 0;
        int currNum = 1;

        while (index < target.length && currNum <= n) {
            int num = target[index];
            if(num == currNum){
                index++;
                currNum++;
                result.add("Push");
            } else {
                result.add("Push");
                result.add("Pop");
                currNum++;
            }
        }
        return result;
    }
}