class Solution {
    public List<String> buildArray(int[] target, int n) {
        List<String> ans = new ArrayList<String>();
        int prev = 0;

        for(int number: target)
        {
            for(int i = 0; i < number - prev - 1; i ++ )
            {
                ans.add("Push");
                ans.add("Pop");
            }
            ans.add("Push");
            prev = number;
        }

        return ans;
    }
}