Challenge Description
Implement int sqrt(int x).
Compute and return the square root of x, where x is guaranteed to be a nonnegative integer.
Since the return type is an integer, the decimal digits are truncated and only the integer part of the result is returned.
Example 1:

Example 2:

Approach with binary search
With binary search, the left
pivot will be the integer value of sqrt. Remember don’t write the code like, this will trigger overflow for some inputs:

Time complexity: $O(log(x))$.

Approach with newton methods
Newtons’ method is a clever method for computing the sqrt value, and we use double
type for the accuracy.
