（POJ 1007）DNA Sorting

 

DNA Sorting

Description

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. 

Input

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.
Output

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.

Sample Input

10 6

AACATGAAGG

TTTTGGCCAA

TTTGGCCAAA

GATCAGATTT

CCCGGGGGGA

ATCGATGCAT

 

Sample Output

 

CCCGGGGGGA

AACATGAAGG

GATCAGATTT

ATCGATGCAT

TTTTGGCCAA

TTTGGCCAAA

Source

East Central North America 1998

 

AC code：

1 #include<stdio.h>
2 #include<string.h>
3 int main()
4 {
5  int m,n,str[108]={0},i,j,s=0,k,temp;
6  char string[108][100],ss[58];
7  scanf("%d %d",&n,&m);
8  for(k=0;k<m;k++)
9  {
10   scanf("%s",string[k]);
11   for(i=0;i<n-1;i++)
12    for(j=i+1;j<n;j++)
13    {
14     if(string[k][i]>string[k][j])
15     str[k]++;
16 }
17 }
18 for(j=0;j<m-1;j++)
19 for(i=0;i<m-1-j;i++)
20 if(str[i]>str[i+1])
21 {
22  temp=str[i];
23  str[i]=str[i+1];
24  str[i+1]=temp;
25  strcpy(ss,string[i]);
26  strcpy(string[i],string[i+1]);
27  strcpy(string[i+1],ss);
28 }
29 for(i=0;i<m;i++)
30 printf("%s/n",string[i],str[i]);
31 getch();
32
33 return 0;
34 }