题解 | #求平方根#

import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param x int整型 
     * @return int整型
     */
    public int sqrt (int x) {
        // write code here
        // System.out.print(Math.log(x));
      long left = 1;
        long right = x;   
        while (true) {
            long  middle = (left + right) / 2;
            if (middle * middle > x) {
                right = middle;
            } else if (middle * middle == x || middle == left) {
                return (int)middle;
            } else if (middle * middle < x) {
                left = middle;
            }
    }
}
}