Java³ÌÐòÁ·Ï°-DNA sorting

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One measure of ``unsortedness'' in a sequence is the number of pairs of entries that are out of order with respect to each other. For instance, in the letter sequence ``DAABEC'', this measure is 5, since D is greater than four letters to its right and E is greater than one letter to its right. This measure is called the number of inversions in the sequence. The sequence ``AACEDGG'' has only one inversion (E and D)---it is nearly sorted---while the sequence ``ZWQM'' has 6 inversions (it is as unsorted as can be---exactly the reverse of sorted).

You are responsible for cataloguing a sequence of DNA strings (sequences containing only the four letters A, C, G, and T). However, you want to catalog them, not in alphabetical order, but rather in order of ``sortedness'', from ``most sorted'' to ``least sorted''. All the strings are of the same length.

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The first line contains two integers: a positive integer n (0 < n <= 50) giving the length of the strings; and a positive integer m (0 < m <= 100) giving the number of strings. These are followed by m lines, each containing a string of length n.
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Output the list of input strings, arranged from ``most sorted'' to ``least sorted''. Since two strings can be equally sorted, then output them according to the orginal order.
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10 6
AACATGAAGG
TTTTGGCCAA
TTTGGCCAAA
GATCAGATTT
CCCGGGGGGA
ATCGATGCAT
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CCCGGGGGGA
AACATGAAGG
GATCAGATTT
ATCGATGCAT
TTTTGGCCAA
TTTGGCCAAA

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import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.util.Arrays;
import java.util.Comparator;
//import java.util.Scanner;
class DNA{
 String value;
 int level;
}
class DNAType implements Comparator<Object>{ 
    public int compare(Object arg0, Object arg1){
     DNA obj1 = (DNA) arg0;
     DNA obj2 = (DNA) arg1;
        return obj1.level - obj2.level;
    }
}
public class Main {
 public static void main(String[] args) throws Exception {
  int i;
  //Scanner cin = new Scanner(System.in);
  DataInputStream cin = new DataInputStream(new BufferedInputStream(System.in));
  //int col = cin.nextInt();
  //int row = cin.nextInt();
  //cin.nextLine();
  String s = new String();
  s = cin.readLine();
  String n[] = s.split(" ");
  int col = Integer.parseInt(n[0]);
  int row = Integer.parseInt(n[1]);
  DNA dna[] = new DNA[row];
  for(i = 0;i < row;++ i){
   String line = new String();
   //line = cin.nextLine();
   line = cin.readLine();
   dna[i] = new DNA();
   dna[i].value = line;
   dna[i].level = getLevel(line);
  }
  DNAType comp = new DNAType();
  Arrays.sort(dna,comp);
  for(i = 0;i < row;++ i){
   System.out.println(dna[i].value);
  }
 }
 private static int getLevel(String line) {
  int i,j,t = 0;
  for(i = 0;i < line.length();++ i){
   for(j = i + 1;j < line.length();++ j){
    if(line.charAt(i) > line.charAt(j)){
     ++ t;
    }
   }
  }
  return t;
 }
}