Poj Solution 1007

http://poj.org/problem?id=1007

import java.util.*;   
  
class DNA   
{   
    private String str = null;   
    private int sortNum = 0;   
       
    public DNA(String input)   
    {   
        str = input;   
           
        int num = 0;   
        for(int i = 0; i < str.length()-1; i++)   
        {   
            for(int j = i+1; j < str.length(); j++)   
                if(str.charAt(i) > str.charAt(j))   
                    num++;   
        }   
        sortNum = num;   
    }   
       
    public int getSortNum()   
    {   
        return sortNum;   
    }   
       
    public String toString()   
    {   
        return str;   
    }   
}   
  
class DNAComparator implements Comparator   
{   
    public int compare(Object o1, Object o2)   
    {   
        DNA d1 = (DNA)o1;   
        DNA d2 = (DNA)o2;   
           
        if(d1.getSortNum() > d2.getSortNum())   
            return 1;   
        else if(d1.getSortNum() == d2.getSortNum())   
            return 0;   
        else  
            return -1;   
    }   
}   
  
public class Main {   
  
    public static void main(String[] args) {   
        Scanner cin = new Scanner(System.in);   
        String[] str = cin.nextLine().split(" ");   
           
        int col = Integer.valueOf(str[0]).intValue();   
        int row = Integer.valueOf(str[1]).intValue();   
        List list = new ArrayList();   
           
        for(int i = 0; i < row; i++)   
        {   
            DNA dna = new DNA(cin.nextLine());   
            list.add(dna);   
        }   
           
        Collections.sort(list, new DNAComparator());   
        print(list);   
    }   
       
    private static void print(List list)   
    {   
        Iterator iter = list.iterator();   
        while(iter.hasNext())   
        {   
            System.out.println(iter.next());   
        }   
    }   
  
}