问题：
Input
The input consists of one or more sets of strings, followed by a final line containing only the value 0. Each set starts with a line containing an integer, n, which is the number of strings in the set, followed by n strings, one per line, sorted in nondescending order by length. None of the strings contain spaces. There is at least one and no more than 15 strings per set. Each string is at most 25 characters long.
Output
For each input set print "SET n" on a line, where n starts at 1, followed by the output set as shown in the sample output.
Sample Input
7
Bo
Pat
Jean
Kevin
Claude
William
Marybeth
6
Jim
Ben
Zoe
Joey
Frederick
Annabelle
5
John
Bill
Fran
Stan
Cece
0
Sample Output
SET 1
Bo
Jean
Claude
Marybeth
William
Kevin
Pat
SET 2
Jim
Zoe
Frederick
Annabelle
Joey
Ben
SET 3
John
Fran
Cece
Stan
Bill
回答：
#include <iostream>
#include <string>
using namespace std;
int main()
{
int n, t = 0, i, j, k;
string word1[16], word2[16];
while(cin >> n && n){
j = k = 0;
for(i=0; i<n; i++)
cin >> word1[i];
for(i=0; i<n; i++)
if(i%2==0){
word2[j] = word1[i];
j++;
}
else {
word2[n-k-1] = word1[i];
k++;
}
cout << "SET " << ++t << endl;
for(i=0; i<n; i++)
cout << word2[i] << endl;
}
return 0;
}