Uolevi has researched his cars fuel consumption. He has noticed that he is able to drive e^x + \sqrt{x} kilometres with x litres of fuel.

What is the least amount of fuel in litres which is enough to drive d kilometres?

Input

Input contains one decimal number, d.

Output

Output the least amount of fuel in litres which if enough to drive d kilometres.

The answer is considered correct if its distance from the correct answer is at most 10^{-6}.

Constraints

• 1 \le d \le 400

Example

Syöte:

123.45

Tuloste:

4.79793355