Python实现Pat 1032. Sharing (25)

题目

Given a collection of number segments, you are supposed to recover the smallest number from them. For example, given {32, 321, 3214, 0229, 87}, we can recover many numbers such like 32-321-3214-0229-87 or 0229-32-87-321-3214 with respect to different orders of combinations of these segments, and the smallest number is 0229-321-3214-32-87.

Input Specification:

Each input file contains one test case. Each case gives a positive integer N (<=10000) followed by N number segments. Each segment contains a non-negative integer of no more than 8 digits. All the numbers in a line are separated by a space.

Output Specification:

For each test case, print the smallest number in one line. Do not output leading zeros.

Sample Input:
5 32 321 3214 0229 87
Sample Output:
22932132143287

解答

排序题，关键在于字符串的大小比较。比较两个字符串大小时如32和321，如果有相同前缀，则删除较长的字符串中的前缀，并比较剩下的数的大小，即32和321的比较结果应该是32和1的比较结果。

from functools import cmp_to_keydef cmpt(s1,s2):     len1=len(s1)     len2=len(s2)     maxl=max(len1,len2)     for i in range(maxl):         if s1[i%len1]!=s2[i%len2]:             return  int(s1[i%len1])-int(s2[i%len2])     else:         return 0line0=input().split(' ')[1:]line0.sort(key=cmp_to_key(cmpt))num=''for e in line0:    num+=ecount=0#剔除无效的‘0’for e in num:    if e=='0':        count+=1    else:        breaknum=num[count:]#特殊情况if not num:    num='0'print (num)

又错了一个小点。不管了