3915 - new DNA sorting
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.
题目输入
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.
题目输出
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.
输入/输出样例
题目输入
10 6 AACATGAAGG TTTTGGCCAA TTTGGCCAAA GATCAGATTT CCCGGGGGGA ATCGATGCAT
题目输出
CCCGGGGGGA AACATGAAGG GATCAGATTT ATCGATGCAT TTTTGGCCAA TTTGGCCAAA
C语言解答
#include <stdio.h> typedef struct DNAMAP { char map[100]; int sum; }DNA; int main() { int m,n,i,j,k; DNA sort[50],t; scanf("%d%d\n",&m,&n); i=0; for (i=0;i<n;i++) { scanf("%s",sort[i].map); sort[i].sum=0; for (j=0;j<m-1;j++) for (k=j+1;k<m;k++) if (sort[i].map[j]>sort[i].map[k]) sort[i].sum++; } for (i=0;i<n-1;i++) for (j=i+1;j<n;j++) if (sort[i].sum>=sort[j].sum) { t=sort[i]; sort[i]=sort[j]; sort[j]=t; } for (i=0;i<n-1;i++) printf("%s\n",sort[i].map); printf("%s",sort[n-1].map); return 0; }
C++解答
#include <iostream> #include <algorithm> using namespace std; typedef struct { string dna; int count; }DNA; DNA dna[101]; int cmp(const void *a,const void *b) { DNA *aa = (DNA *)a; DNA *bb = (DNA *)b; return aa->count-bb->count; } int main() { int n,m; char c; cin>>n>>m; for(int i = 0; i < m; i++) { cin>>dna[i].dna; dna[i].count = 0; for(int j = 0; j < n; j++) for(int k = j+1; k < n; k++) { if(dna[i].dna[j]>dna[i].dna[k]) dna[i].count++; } } qsort(dna,m,sizeof(dna[0]),cmp); for(int i = 0; i < m; i++) cout<<dna[i].dna<<endl; return 0; }