[LeetCode] Sqrt(x)

Implement int sqrt(int x).

Compute and return the square root of x.

牛顿迭代法

class Solution {public:    int sqrt(int x) {        if(x == 0) return 0;        double pre,cur = 1;        do{            pre = cur;            cur = x / (2 * pre) + pre / 2.0;        }while(abs(cur - pre) > 0.00001);        return int(cur);    }   };