Geekily yours!

Geekily yours!
Given an array of integers. This array denotes 'our' own ascending order of the elements. So if the array is {2,3,1,4}, by mathematics we can say that 2<3<1<4. Given another array, sort this new array in 'our' ascending order.
Let's say the new array is {1,2,4,3,5,4,9,2}, output will be {2,2,3,1,4,4,5,9}. Note that since 5 and 9 do not occur, they are sorted by actual ascending order at the end.

    public static ArrayList<Integer> sort(int customSortList[], Integer arr[]){

        Map<Integer, Integer> mp = new LinkedHashMap<Integer, Integer>();

        for(int i=0;i<customSortList.length;i++) {

            mp.put(customSortList[i], i);

        }

        List<Integer> a = Arrays.asList(arr);

        Collections.sort(a); // not occur, sort by actual order.

        arr = a.toArray(new Integer[arr.length]);

        ArrayList<Integer> newArr = new ArrayList<Integer> (arr.length);

 

        Iterator it = mp.entrySet().iterator();

        while (it.hasNext()){

            Map.Entry pairs = (Map.Entry)it.next();

            int key = (Integer)pairs.getKey();

            for(int i=0;i<a.size();i++){

                if(a.get(i)==key){

                    newArr.add(key);

                }

            }

        }

        for(int i=0;i<a.size();i++){

            if (!newArr.contains(a.get(i))){

                newArr.add(a.get(i));

            }

        }

        return newArr;

    }

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