C. Creative archery
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Maxim is a big fan of all kinds of games. This time he is playing a game called "Minecraft".

This time he came up with a great idea to build a huge target and practice archery. According to Maxim's plan, the target will look like a square with an even side length $$$x$$$, and each inner layer is painted either white or red, with the colors alternating (for better understanding, see the picture):

Example of an $$$8 \times 8$$$ target.
Example of a $$$4 \times 4$$$ target.

Maxim also wants to make this target out of wool, but he doesn't have a lot of red wool, specifically $$$n$$$ blocks. Help Maxim figure out the maximum side length $$$x$$$ his target can have!

Input

The only line contains a single integer $$$n$$$ ($$$4 \le n \le 1000$$$).

Output

Output a single integer $$$x$$$ - the answer to the problem.

Examples
Input
5
Output
4
Input
12
Output
6