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Description

Goldbach's conjecture is one of the three major mathematical problems in modern times. It states that every even number greater than $2$ can be expressed as the sum of two prime numbers. For example, $4=2+2$, $6=3+3$, $8=3+5$, $10=3+7$.
Please define a function to determine if a number is prime, and use it to verify that all even numbers between $4$ and $n$ can be decomposed into the sum of two prime numbers, where $n≥4$.

Input Format

One line containing an integer $n$.

Output Format

Output several lines, each containing an equation showing how an even number between $4$ and $n$ is decomposed into the sum of two prime numbers. If an even number does not satisfy this condition, output "Verification failed!".

Sample

10

4=2+2
6=3+3
8=3+5
10=3+7