High Precision Factorial Sum

Given a positive integer n (with n ≤ 50), compute the sum

\( S = 1! + 2! + 3! + \cdots + n! \)

where the factorial ! is defined as

\( n! = n \times (n-1) \times (n-2) \times \cdots \times 1 \)

For example, \(5! = 5 \times 4 \times 3 \times 2 \times 1 = 120\).

Your task is to compute S using high precision arithmetic to handle very large numbers.

inputFormat

The input consists of a single integer n (1 ≤ n ≤ 50).

outputFormat

Output the high precision result of the sum \( S = 1! + 2! + \cdots + n! \).

sample

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