Sum of Unique Prime Factors

In this problem, you are given a positive integer (n). Your task is to find all the unique prime factors of (n) and compute their sum. For example, if (n = 10), the prime factors are (2) and (5), and the sum is (7). Make sure to read the input from standard input and output the result to standard output.

inputFormat

A single integer (n) (where (n \ge 1)) is provided via standard input.

outputFormat

Output a single integer which is the sum of all unique prime factors of (n) to standard output.## sample

10

7