#include <stdio.h>
#include <iostream>
#include <string>
#include <cctype>
int main(){
using namespace std;
int n;
scanf("%d", &n);
string s;
while(n > 0){
	cin.get();
	cin.clear();
	getline(cin, s);
	int l = s.length();
	char cs[l];
	int l2 = 0;
	for(int i = 0; i < l; i++){
		if(int(s[i]) != 32) cs[l2++] = toupper(s[i]); 
		}
	char fin[l2];
	int togo = l2;
	int posun = 0;
	int pos = 0;
	while(togo > 0){
		pos = posun;
		posun++;
		while(togo > 0 && pos < l2){
			fin[pos] = cs[l2-togo];
			pos += n;
			togo--;
			}
		}
	for(int i = 0; i < l2; i++) cout << fin[i];
	cout << endl;
	scanf("%d", &n);
	}
}