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Design Tutorial: Learn from Math

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One way to create a task is to learn from math. You can generate some random math statement or modify some theorems to get something new and build a new task from that.

For example, there is a statement called the "Goldbach's conjecture". It says: "each even number no less than four can be expressed as the sum of two primes". Let's modify it. How about a statement like that: "each integer no less than 12 can be expressed as the sum of two composite numbers." Not like the Goldbach's conjecture, I can prove this theorem.

You are given an integer n no less than 12, express it as a sum of two composite numbers.


The only line contains an integer n (12 ≤ n ≤ 106).


Output two composite integers x and y (1 < x, y < n) such that x + y = n. If there are multiple solutions, you can output any of them.

Sample Input:


Sample Output:

4 8

Sample Input:


Sample Output:

6 9

Sample Input:


Sample Output:

8 15

Sample Input:


Sample Output:

500000 500000


In the first example, 12 = 4 + 8 and both 4, 8 are composite numbers. You can output "6 6" or "8 4" as well.

In the second example, 15 = 6 + 9. Note that you can't output "1 14" because 1 is not a composite number.



Provider CodeForces

Origin Codeforces Round #270

Code CF472A


mathnumber theory

Submitted 18

Passed 13

AC Rate 72.22%

Date 03/03/2019 22:44:57


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