leetcode 第69题 Sqrt(x)

Implement int sqrt(int x).

Compute and return the square root of x.

思路：我们可以用牛顿法来求解。

C++代码实现：

class Solution {
public:
    int mySqrt(int x) {
        double result = 1.0;
        double delta = 1e-5;
        while(abs(result*result - x) > delta){
            result = (result + x/result)/2;
        }
        return result;
    }
};