Frequency Sort Example

import java.util.LinkedHashMap;

/*
 * Given an array of integers, sort the array according to frequency of elements.
 * For example, if the input array is {2, 3, 2, 4, 5, 12, 2, 3, 3, 3, 12}, then
 * modify the array to {3, 3, 3, 3, 2, 2, 2, 12, 12, 4, 5}.
 */
public class frequencySort1 {

    public static void main(String[] args) {
        int[] unsortedArray = { 2,12,3,2,4,2,3,3,3,12,5 };

        LinkedHashMap<Integer, Integer> valueAndItsCount = new LinkedHashMap<Integer, Integer>();

        for(int x : unsortedArray) {
            if(valueAndItsCount.containsKey(x)) {
                int xCount = valueAndItsCount.get(x);
                xCount++;
                valueAndItsCount.put(x, xCount);
            }
            else {
                valueAndItsCount.put(x, 1);
            }
        }

        int maxCount = 0;
        int theKey = 0;
        while(!valueAndItsCount.isEmpty()) {


            for(int x : valueAndItsCount.keySet()) {
                if(valueAndItsCount.get(x) > maxCount) {
                    maxCount = valueAndItsCount.get(x);
                    theKey = x;
                }
            }

            for(int i=0; i < maxCount; i++) {
                System.out.print(theKey + " ");
            }
            valueAndItsCount.remove(theKey);
            maxCount = 0;
        }

    } //end main
}