[POJ] 1007 -> DNA Sorting

DNA Sorting

Time Limit: 1000MS		Memory Limit: 10000K
Total Submissions: 87856		Accepted: 35306

DescriptionOne 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 fourletters 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.InputThe 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 stringof length n.OutputOutput 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

Code:

#include <iostream>#include <algorithm>#include <string>using namespace std;int measure(string s){int res = 0;int n = s.length();for (int i = 0; i < n; i++)for (int j = i + 1; j < n; j++)if (s[i]>s[j]) ++res;return res;}bool cmp(string s1, string s2){return measure(s1) < measure(s2);}int main(){int n, m;string s[101];cin >> n >> m;for (int i = 0; i < m; i++)cin >> s[i];sort(s, s + m, cmp);for (int i = 0; i < m; i++)cout << s[i] <<endl;return 0;}