Arithmetic square root (sqrt)

Description

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In mathematics, (sqrt{x}) represents the arithmetic square root of (x). If (sqrt{x} = y), then (y ge 0) and (y^2 = x).
Given a non-negative integer (x), request the integer part of (sqrt{x}).

Format

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Input

The first line contains a non-negative integer (x).

Output

Output an integer per line, which is the answer.

Sample

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Input1

3

Output1

1

Input2

4

Output2

2

Input3

121

Output3

11

Hint

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Test point number	(x)
(1 sim 3)	(leq 10^9)
(4 sim 6)	(leq 10^{12})
(7 sim 10)	(leq 10^{18})

Sample Code

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Code is not available!