# -*- coding: utf-8 -*-


if __name__ == "__main__":
    m=input()
    n=input()
    x=input()
    #vasiot kod pisuvajte go tuka

    table = {}

    for value in range(m,n+1):
        key = value**3
        table[key] = value




    if x in table:
        print table[x]
    else:
        print "nema podatoci"


    table_tuples = [(k,v) for k,v in sorted(table.items())]
    print(table_tuples)