DNA Sorting-PKU ACM 1007

题目来源：http://acm.pku.edu.cn/JudgeOnline/problem?id=1007

 

算法比较呆，就是首先算出每个字符串的逆序字母的个数，然后将个数放入一个multimap中，直接排好序了，然后输出。

 

 #include <iostream> #include <string> #include <map> #include <algorithm> using namespace std; int main() { int length,num; multimap<int,int,less<int>> multi; cin >> length >> num; cin.get(); string *c; c = new string[num]; int *total=new int[num]; int i=0,j,k; for(i=0;i<num;i++) total[i]=0; i=0; while(num > 0) { getline(cin,c[i]); for(j=0;j<length;j++) for(k=j;k<length;k++) { if(c[i][j]>c[i][k]) total[i]++; } multi.insert(make_pair(total[i],i)); i++; num--; } for(multimap<int,int,less<int>>::iterator it=multi.begin();it!=multi.end();it++) cout << c[(*it).second] << endl; return 0; }

 

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DNA Sorting

Time Limit: 1000MS		Memory Limit: 10000K
Total Submissions: 44012		Accepted: 17106

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