Sqrt(x)

Sqrt(x)

Given a non-negative integer x, return the square root of x rounded down to the nearest integer. The returned integer should be non-negative as well.

You must not use any built-in exponent function or operator (e.g., Math.sqrt, x ** 0.5, pow(x, 0.5)).

Examples

Example 1:

Input: x = 4
Output: 2
Explanation: The square root of 4 is 2, so we return 2.

Example 2:

Input: x = 8
Output: 2
Explanation: The square root of 8 is 2.82842..., and since we round it down to the nearest integer, 2 is returned.

Example 3:

Input: x = 0
Output: 0

Constraints

• 0 <= x <= 2^31 - 1

Expected Complexity

• Time: O(log x)
• Space: O(1)