2.2

#include <iostream>

using namespace std;

main()
{
//2.2
    int k;
    cin >> k;
    int n;
    cin >> n;
    //ma_foykarznrtitu_ima_
    string S;
    cin >> S;

    int kolumny = n/k;
    char T[k][kolumny];

    int licz = 0;
        for(int i = 0; i < k; i++)
            {
                for(int j = 0; j < kolumny; j++)
                {
                    T[i][j] = S[licz++];
                //  cout << T[i][j];
                }
            }

    bool wDol = true;
    int i = 0;
    int j = 0;
    licz = 0;

    while(licz!=n)
    {
        if(wDol)
        {
            S[licz++] = T[i][j];
            i++;
        }
        else
        {
            S[licz++] = T[i][j];
            i--;
        }

        if(i==k-1)
        {
            S[licz++] = T[i][j];
            j++;
            wDol = false;
        }

        if(i==0)
        {
            S[licz++] = T[i][j];
            j++;
            wDol = true;
        }
    };

    cout << S;


}