LeetCode—367. Valid Perfect Square

Valid Perfect Square思路：牛顿二分法，注意边界判定。

GitHub地址：https://github.com/corpsepiges/leetcode

点此进入

public class Solution {    public boolean isPerfectSquare(int num) {        int x=num;        while(true){            int t=(x+num/x)/2;            if (t*t==num||(t-1)*(t-1)==num||(t+1)*(t+1)==num) {                return true;            }            if (x==t||x==t-1||x==t+1) {                return false;            }            x=t;        }    }}