In the event of technical difficulties with Szkopuł, please contact us via email at [email protected].
If you would like to talk about tasks, solutions or technical problems, please visit our Discord servers. They are moderated by the community, but members of the support team are also active there.
Psst... Ruszyły zawody olimpiady informatycznej dla uczniów szkół podstawowych i średnich. Zadania na tych konkursach są bardzo podobne do zadań, które rozwiązujesz, tutaj, na Szkopule. Zobacz więcej:
- dla uczniów szkół podstawowych: oij.edu.pl/start/
- dla uczniów szkół średnich: oi.edu.pl/l/jak_zaczac/
In this problem we recall the great mathematician Leonhard Euler (1707-1783)
and investigate his well-known totient function, .
The value of for positive integer is the number of integers ()
that are coprime with .
Two integers are called coprime if their only common positive divisor is 1.
For example, we have , since 1 and 5 are coprime with 6,
whereas 2, 3, 4 and 6 are not.
A problem that could have been stated by Euler is as follows:
given a positive integer , find all positive integers that satisfy the equation:
Input
The first line of input contains one integer () that denotes the number of test cases.
lines follow with descriptions of respective test cases.
Each such description consists of a single integer ().
Output
Your program should output the answers to the respective test cases.
For each test case it should write two lines.
The first line should contain the number of solutions of the equation.
The second line should contain all solutions listed in increasing order.
If the equation does not have any solution, for the corresponding test case
your program should write an empty second line.