poj 2013 Symmetric Order

#include <iostream>
#include <string>
using namespace std;
int main()
{
    char str[20][30];
    int flag[20];
    int n,t=1,i;
    while(cin>>n&&n)
    {
        cout<<"SET "<<t++<<endl;
        fill(flag,flag+20,1);
        for(int i=1;i<=n;i++)
        {
            cin>>str[i];
            if(i%2==1)
            {
                flag[i]=0;
                cout<<str[i]<<endl;
            }
        }
        for(int i=n;i>=1;i--)
            if(flag[i]==1)
                cout<<str[i]<<endl;
    }
    return 0;
}