#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <utility>
#include <stack>
#include <vector>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <list>

#define FOR(a,b,c) for(int a=b;a<=c;a++) 
#define SIZEOF(a) (sizeof(a)/sizeof(a[0]))
#define FORARR(i,a) for(unsigned i=0; i<SIZEOF(a);i++)
#define FOREACH(a,b) for(_typeof((b).begin()) a=(b).begin(); a!=(b).end();a++)
#define GETI(a) scanf("%d", &a)

using namespace std;

int main(void)
{
	int N;
	while (GETI(N) == 1 && N > 0) {
		string str;
		char c;
		scanf("%c", &c);
		do {
			scanf("%c", &c);
#ifdef DEBUG
		cout << "c: " << c << endl;
#endif
			if (isspace(c)) continue;
			c = toupper(c);
			str += c;
			
		} while (c != '\n');
		
		int strpos = 0;
		
#ifdef DEBUG
		cout << "str: " << str << endl;
#endif
		char result[10001] = {0};
		FOR(offset,0,N-1) {
			for (int i=0; i+offset < str.size(); i+=N) {
				result[i+offset] = str[ strpos++ ];
			}
		}
		
		cout << result << endl;

/*
		
		list<int> positions;
		FOR(i,0,str.length()-1) {
			positions.push_back(i);
		}
		
		char result[10001] = {0};
		
		int strpos = 0;
		
		// naskladat pismena
		while (!positions.empty()) {
			list<int>::iterator i = positions.begin();
#ifdef DEBUG
			cout << "i: " << *i << endl;
#endif
			while (i != positions.end()) {
				result[ *i ] = str[ strpos++ ];
				// posunout i o N pozic dal
				list<int>::iterator j = i;
				i++;
				positions.erase(j);
				FOR(k,0,N-2) {
					if (i == positions.end()) break;
					i++;
				}
			}
		}
		cout << result << endl;
*/		
	}
	

	return 0;
}