Java程序練習-DNA sorting

描述
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.

輸入
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.
輸出
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.
樣例輸入
10 6
AACATGAAGG
TTTTGGCCAA
TTTGGCCAAA
GATCAGATTT
CCCGGGGGGA
ATCGATGCAT
樣例輸出
CCCGGGGGGA
AACATGAAGG
GATCAGATTT
ATCGATGCAT
TTTTGGCCAA
TTTGGCCAAA

參考代碼

1. import java.io.BufferedInputStream;
2. import java.io.DataInputStream;
3. import java.util.Arrays;
4. import java.util.Comparator;
5. //import java.util.Scanner;
6. class DNA{
7. String value;
8. int level;
9. }
10. class DNAType implements Comparator<Object>{
11. public int compare(Object arg0, Object arg1){
12. DNA obj1 = (DNA) arg0;
13. DNA obj2 = (DNA) arg1;
14. return obj1.level - obj2.level;
15. }
16. }
17. public class Main {
18. public static void main(String[] args) throws Exception {
19. int i;
20. //Scanner cin = new Scanner(System.in);
21. DataInputStream cin = new DataInputStream(new BufferedInputStream(System.in));
22. //int col = cin.nextInt();
23. //int row = cin.nextInt();
24. //cin.nextLine();
25. String s = new String();
26. s = cin.readLine();
27. String n[] = s.split(" ");
28. int col = Integer.parseInt(n[0]);
29. int row = Integer.parseInt(n[1]);
30. DNA dna[] = new DNA[row];
31. for(i = 0;i < row;++ i){
32. String line = new String();
33. //line = cin.nextLine();
34. line = cin.readLine();
35. dna[i] = new DNA();
36. dna[i].value = line;
37. dna[i].level = getLevel(line);
38. }
39. DNAType comp = new DNAType();
40. Arrays.sort(dna,comp);
41. for(i = 0;i < row;++ i){
42. System.out.println(dna[i].value);
43. }
44. }
45. private static int getLevel(String line) {
46. int i,j,t = 0;
47. for(i = 0;i < line.length();++ i){
48. for(j = i + 1;j < line.length();++ j){
49. if(line.charAt(i) > line.charAt(j)){
50. ++ t;
51. }
52. }
53. }
54. return t;
55. }
56. }