#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

void deleteSpacesAndDoUpperCase(char * str, char * newStr, int strl) {
	
	int i; int j = 0;
	
	for (i=0; i < strl; i++) {
				
		if (! isspace(str[i])) {

			newStr[j++] = toupper(str[i]);
		}
		
	}

	newStr[j] = 0;	
}

int main()
{
	int pocet = 0;
	char retezec[10001];
	char vysledek[10001];
	int i = 0;
	int j = 0;	
	int strl = 0;
	int k;

	while((scanf("%d", &pocet))  && pocet > 0) {
		k = 0;		

		getchar();
		fgets(retezec, 10001, stdin);		
		strl = strlen(retezec);
		
		deleteSpacesAndDoUpperCase(retezec, vysledek, strl);
	
		strl = strlen(vysledek);

		for(i = 0; i <= pocet - 1; i++)
		{
			j = i;
			while (j < strl)
			{
				retezec[j] =  vysledek[k++];
				j += pocet;
			}
		}
		retezec[k] = 0;
		printf("%s\n", retezec);
	}	
	
	return 0;
}