leetcode -- happy number 快乐数
来源:互联网 发布:淘宝产品详情怎么设置 编辑:程序博客网 时间:2024/06/05 17:27
Write an algorithm to determine if a number is "happy".
A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not include 1. Those numbers for which this process ends in 1 are happy numbers.
Example: 19 is a happy number
- 12 + 92 = 82
- 82 + 22 = 68
- 62 + 82 = 100
- 12 + 02 + 02 = 1
方法解析:
显然,set集合适合于判断各个数位的平方和是否重复,若已存在则false。
public class Solution {
public boolean isHappy(int n) {
HashSet set = new HashSet();
int temp = 0;
int sum = 0;
while (!set.contains(n)) {
set.add(n);
sum = 0;
while(n != 0) {
temp = n % 10;
sum += temp * temp;
n = temp / 10;
}
if (sum == 1) {
return true;
}
n = sum;
}
return false;
}
}
- Leetcode 快乐数Happy Number
- leetcode -- happy number 快乐数
- (LeetCode)Happy Number -- 寻找快乐数
- [LeetCode]202. Happy Number 快乐数
- 202.leetcode Happy Number(easy)[数学 快乐数]
- uva10591 - Happy Number(快乐的数)
- LeetCode202——Happy Number快乐数
- LeetCode 202. Happy Number(快乐数字)
- 488.Happy Number-快乐数(容易题)
- LeetCode OJ 之 Happy Number (happy数)
- leetcode系列(21)happy number 欢乐数
- LeetCode 202 Happy Number(开心数)(vector、unordered_set)
- [leetcode] Happy Number
- leetcode: Happy Number
- [LeetCode] Happy Number
- [LeetCode]Happy Number
- LeetCode 202 Happy Number
- LeetCode OJ Happy Number
- 浅析人脸检测之Haar分类器方法:Haar特征、积分图、 AdaBoost 、级联
- C++笔试面试真题回顾与知识点总结
- POJ 3422 Kaka's Matrix Travels(费用流)
- POJ1066
- Windows编程之如何查看CPU内核数以及如何将任务制定到不同的内核上
- leetcode -- happy number 快乐数
- 经典JavaScript正则表达式实战
- c++重载函数调用运算符
- 《剑指offer》牛客网java题解-二进制中1的个数
- APDS9930
- hdu 1257 最少拦截系统(贪心)
- 应用CTreeCtrl控件的技巧
- 面部表情训练~
- 安装Caffe-Master(GPU和CPU)