uva 10905 - Children's Game

4thIIUC Inter-University Programming Contest, 2005
A	Children’s Game
	Input: standard input Output: standard output
	Problemsetter: Md. Kamruzzaman

There are lots of number games for children. These games are pretty easy to play but not so easy to make. We will discuss about an interesting game here. Each player will be given N positive integer. (S)He can make a big integer by appending those integers after one another. Such as if there are 4 integers as 123, 124, 56, 90 then the following integers can be made – 1231245690, 1241235690, 5612312490, 9012312456, 9056124123 etc. In fact 24 such integers can be made. But one thing is sure that 9056124123 is the largest possible integer which can be made.

You may think that it’s very easy to find out the answer but will it be easy for a child who has just got the idea of number?

Input

Each input starts with a positive integer N (≤ 50). In next lines there are N positive integers. Input is terminated by N = 0, which should not be processed.

Output

For each input set, you have to print the largest possible integer which can be made by appending all the N integers.

Sample Input	Output for Sample Input
4 123 124 56 90 5 123 124 56 90 9 5 9 9 9 9 9 0	9056124123 99056124123 99999

 

直接按單個數字assic大小排序再連接會導致錯誤是因爲，對於前綴相同長度不等的數字無法判斷如何連接，對於前綴不同或者長度相同的可以直接連接

如

98       9 98 979   ASSIC  98>979>9
979
9 

123    123 12 1    ASSIC 123>12>1 
12 
1 

因此對所有兩兩連接的assic排序,可以保證前綴大的再前面而且連接之後大的也在前面

#include<string.h>
#include<stdio.h>
int main()
{
 int i,j,n;
 char s[51][100],ch1[200],ch2[200],temp[100];
 while (scanf("%d",&n),n)
 {
  for (i=1;i<=n;i++)
      scanf("%s",&s[i]);
  for (i=1;i<n;i++)
  for (j=i+1;j<=n;j++)
  {
   strcpy(ch1,s[i]);
   strcpy(ch2,s[j]);
   strcat(ch1,s[j]);
   strcat(ch2,s[i]);
   if (strcmp(ch1,ch2)<0) {strcpy(temp,s[i]); strcpy(s[i],s[j]); strcpy(s[j],temp);}
  }
  for (i=1;i<=n;i++)
  printf("%s",s[i]);
  printf("\n");
 }
 return 0;
}