Description

Write a program to calculate integer square roots.

Input

The input is read from a text file named squint.in. Its only line consists of an integer 0 < = n < 2^63 .

Output

Its only line consists of the smallest nonnegative integer q such that q^2 >= n .

Samples

122333444455555

11060446

Limitation

sqrt(122333444455555)=11060445.038765619 .