def merge_the_tools(string, k):
    s = string
    n = len(s)
    sn = n//k
    ss = []
    for x in range(0, n, k):
        ss.append(s[x:(x + k)])
    for x in range(sn):
        sss = []
        for y in range(k):
            if ss[x][y] not in sss:
                sss.append(ss[x][y])
        print(''.join(sss))
if __name__ == '__main__':
    string, k = input(), int(input())
    merge_the_tools(string, k)