#include <iostream>
#include <string>
#include <cstring>
#include <cmath>
using namespace std;

void nacitaj(string& s)
{
    char c;
    cin.get(c);
    while(c!='\n')
    {
        if(c!=' ') s.push_back(toupper(c));
        cin.get(c);
    }
}

int main()
{
    string s,vys;
    int skok;

    int x;

    vys.resize(10000);

    while(true)
    {
        cin >> skok;
        if(skok == 0) return 0;
        if(skok!=0) cin.get();
        s.erase(s.begin(),s.end());
        nacitaj(s);
        x=0;

        vys.erase(vys.begin(),vys.end());
        vys.resize(10000);

        if(s.length()<=skok) cout << s << endl;
        else
        {

        for (int i=0;i<=skok;i++) {
                for(int j=1+i;j<=s.length();j=j+skok) {
                    if(x>=s.length()) break;
                    //cout << j << endl;
                    vys[j] = s[x];
                    //cout<< s[x];
                    x++;
                }

        }

        }


        if(not (s.length()<=skok)) cout << vys << endl;
    }

}