Task

For each given a number N, the integer S is called integer square root of N if S x S <= N and (S+1) x (S+1) > N.

In other words, S = Math.floor(Math.sqrt(N))

Your task is to calculate the integer square root of a given Number.

Note: Input is given in string format. That is, the Number may be very very large ;-)

Example

For: Number = "4", result = "2".

For: Number = "17", result = "4".

For: Number = "101", result = "10".

For: Number = "23232328323215435345345345343458098856756556809400840980980980980809092343243243243243098799634", result = "152421548093487868711992623730429930751178496967".

Input/Output

• [input] string Number

number in decimal form. 0 < Number < 10^100

• [output] a string

integer squareroot of Number.