二分法实现开方

//
// Created by LK on 2020/3/21.

#include <iostream>
#include <cmath>
using namespace std;
// 不用sqrt库函数，实现开方
// 思路用二分法，比如2，  left=0，right = 2， 然后
class Solution
{
public:
    double Sqrt(double n)
    {
//        if(n == 1)
//            return n;
        double left = 0.0;
        double hight = n;
        double p = 1e-5;  // 此处为精度，当满足该精度时返回近似值
        double mid = (left + hight)/2.0;
        while (fabs(mid * mid - n) > p)  // 精度比较
        {
            if(mid * mid > n)
                hight = mid;
            else if (mid * mid < n)
                left = mid;
            else
                return mid;
            mid = (left + hight)/2.0;
        }
        return mid;
    }
};
int main()
{
    Solution s;
    cout << s.Sqrt(4);
    return 0;
}