Sorter.java

// Given an array with n objects colored red, white or blue,
// sort them so that objects of the same color are adjacent, with the colors in the order red, white and blue.

// Here, we will use the integers 0, 1, and 2 to represent the color red, white, and blue respectively.

// Note: Using library sort function is not allowed.

// Example :

// Input : [0 1 2 0 1 2]
// Modify array so that it becomes : [0 0 1 1 2 2]
public class Solution {
    
    int[] count = new int[3];
    public void sortColors(ArrayList<Integer> a) {

        for(int i: a) {
            count[i]++;
        }
        a.clear();
    
        for (int i=0; i<=2; i++) {
            int count = 0;
            int noOfEntity = count[i];
            while (count < noOfEntity) {
                a.add(i);
                count++;
            }
        }
        
    }
}