Sum of Prime Factors Bonus Metric

A company rewards its most efficient employees with a bonus based on the metric (W), which is defined as the sum of all prime factors of an employee's unique identification number (ID). Given (ID = n), compute (W) using the formula: (W = \sum_{p \mid n} p), where each prime factor (p) is added as many times as it divides (n). Note that if (n = 1), then (W = 0).

inputFormat

Input consists of a single line containing a positive integer (n) which represents the employee's unique identification number.

outputFormat

Output a single integer which is the sum of all prime factors of (n) computed as described above.## sample

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