CF612A The Text Splitting

You are given the string $ s $ of length $ n $ and the numbers $ p,q $ . Split the string $ s $ to pieces of length $ p $ and $ q $ . For example, the string "Hello" for $ p=2 $ , $ q=3 $ can be split to the two strings "Hel" and "lo" or to the two strings "He" and "llo". Note it is allowed to split the string $ s $ to the strings only of length $ p $ or to the strings only of length $ q $ (see the second sample test).

The first line contains three positive integers $ n,p,q $ ( $ 1

If it's impossible to split the string $ s $ to the strings of length $ p $ and $ q $ print the only number "-1". Otherwise in the first line print integer $ k $ — the number of strings in partition of $ s $ . Each of the next $ k $ lines should contain the strings in partition. Each string should be of the length $ p $ or $ q $ . The string should be in order of their appearing in string $ s $ — from left to right. If there are several solutions print any of them.