class A {
    public static void main(String[] a) {
        new T().f("Hi, world");
        System.out.println();
        new T().f("Hi, world! Hello");
        System.out.println();
        new T().f("Lorem ipsum dolor sit amt");
        System.out.println();
        new T().f("H");
    }
 
    static class T {
        void f(String s) {
            for (int i = -1, k = (int) Math.sqrt(s.length()); ++i < k; ) {
                System.out.println(s.substring(i * k, i * k + k));
            }
        }
 
    }
}

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