Description

Using the formula $e = 1 + \frac{1}{1!} + \frac{1}{2!} + \frac{1}{3!} + \dots + \frac{1}{n!}$, calculate the value of $e$, preserving 10 decimal places.

Input Format

The input consists of a single line containing an integer $n$ ($2 \leq n \leq 15$), indicating that the summation for calculating $e$ includes terms up to $\frac{1}{n!}$.

Output Format

The output consists of a single line displaying the computed value of $e$, formatted to 10 decimal places.

10

2.7182818011