leetcode：Sqrt(x) 【Java】

一、问题描述

Implement int sqrt(int x).

Compute and return the square root of x.

二、问题分析

返回整型的最接近的平方根。

三、算法代码

public class Solution {    public int mySqrt(int x) {        if(x < 2){             return x;        }                int left = 1;        int right = x / 2;        int middle = -1;        int last_middle = -1;        while(left <= right){            middle = left + (right - left) / 2;            if(x / middle > middle){                left = middle + 1;                last_middle = middle; //最接近的平方根            }else if(x / middle < middle){                right = middle - 1;            }else{                return middle;            }        }        return last_middle;    }}