POJ 1007 DNA Sorting

DNA Sorting

Time Limit: 1000MS		Memory Limit: 10000K
Total Submissions: 63725		Accepted: 25159

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

c++代码：

#include<iostream>

#include<cstring>

#include<cstdlib>

using namespace std;

const int MAX=105;

struct DNA{

char str[55];

int measures;

};

int dlen(char *str){

int cnt=0;

for(int i=0;i<strlen(str);i++)

for(int j=i+1;j<strlen(str);j++){

if(str[i]>str[j])cnt++;

}

return cnt;

}

DNA dna[MAX];

int cmp(const void *va,const void *vb){

DNA*a,*b;

a=(DNA*)va;

b=(DNA*)vb;

if(a->measures > b->measures)return 1;

else if(a->measures < b->measures)return -1;

return 0;

}

int main(){

int len,n;

cin>>len>>n;

for(int i=0;i<n;i++){cin>>dna[i].str;dna[i].measures=dlen(dna[i].str);}

qsort(dna,n,sizeof(DNA),cmp);

for(int i=0;i<n;i++)cout<<dna[i].str<<endl;

return 0;

}

java代码如下：

import java.util.Arrays;

import java.util.Comparator;

import java.util.Scanner;

public class Main {

private String str;

private int cnt;

public void len() {

int size = str.length();

for (int i = 0; i < size; i++)

for (int j = i + 1; j < size; j++) {

if (str.charAt(i) > str.charAt(j))

this.cnt++;

}

}

public Main() {

this.cnt = 0;

}

public static void main(String[] args) {

Scanner in = new Scanner(System.in);

int len = in.nextInt();

int n = in.nextInt();

Main[] dnaSortings = new Main
;

for (int i = 0; i < n; i++) {

dnaSortings[i]=new Main();

}

for (int i = 0; i < n; i++) {

dnaSortings[i].str = in.next();

dnaSortings[i].len();

}

Comparator<? super Main> c = new Comparator<Main>() {

@Override

public int compare(Main o1, Main o2) {

if (o1.cnt > o2.cnt) {

return 1;

} else if (o1.cnt < o2.cnt) {

return -1;

}

return 0;

}

};

Arrays.sort(dnaSortings, c);

for (int i = 0; i < n; i++) {

System.out.println(dnaSortings[i].str);

}

}

}