单点时限: 2.0 sec
内存限制: 256 MB
Write a program to calculate integer square roots.
Its only line consists of an integer $0 \leqslant n \leq 2^{63}$ .
Its only line consists of the smallest nonnegative integer $q$ such that $q^2 \geqslant n$ .
122333444455555
11060446
$122333444455555^{0.5} ≈ 11060445.038765619$