poj 2039

#include<cstdio>#include<cstring>int main(){int n;char str[1000];while(~scanf("%d",&n)&&n){scanf("%s",str);int len=strlen(str);for(int i=0;i<n;i++)for(int j=0;j<len/n;j++)if(j&1)printf("%c",str[n-1-i+n*j]);elseprintf("%c",str[i+n*j]);printf("\n");}return 0; }