#C3638. Prime Pair Sum Problem
Prime Pair Sum Problem
Prime Pair Sum Problem
Given an integer \(n\), your task is to find two prime numbers \(p\) and \(q\) such that \(p+q=n\). If more than one pair exists, choose the pair with the smallest absolute difference \(|p-q|\). If there are still multiple solutions, choose the pair where the smaller prime is the smallest. If no such pair exists, output an empty array, denoted as []
.
Examples:
- For \(n=10\), the answer is
5 5
because \(5+5=10\) and the difference \(|5-5|=0\) is minimal. - For \(n=12\), the answer is
5 7
since \(5+7=12\). - For \(n=4\), the answer is
2 2
. - For \(n=20\), the answer is
7 13
. - For \(n=1\) or \(n=27\), no valid pair exists so output
[]
.
inputFormat
The input consists of a single integer \(n\) (\(0 \le n \le 10^6\)). The number is provided via standard input.
outputFormat
If there exists a valid pair of prime numbers \(p\) and \(q\) such that \(p+q=n\), output the two numbers separated by a space via standard output. Otherwise, output []
.
10
5 5