题解 | #求平方根#

二分查找的思路。

import java.util.*;


public class Solution {
    /**
     * 
     * @param x int整型 
     * @return int整型
     */
    public int sqrt (int x) {
        // write code here
        if (x <= 1) {
            return x;
        }
        int min = 0;
        int max = x;
        int result = 0;
        while (min <= max) {
            int mid = (min + max) / 2;

            if (mid <= x / mid) {
                result = mid;
                min = mid + 1;
            } else {
                max = mid - 1;
            }
        }
        return result;
    }
}