zoukankan      html  css  js  c++  java
  • Happy Number

    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
    public class Solution {
        
        private Set<Integer> num_set = new HashSet<Integer>();
        
        public int getSum(int n) {
            int sum = 0;
            while(n!=0) {
                sum = sum+(n%10)*(n%10);
                n = n/10;
            }
            return sum;
        }
        
        public boolean isHappy(int n) {
            if(num_set.contains(n)) return false;
            else num_set.add(n);
            int sum = getSum(n);
            if(sum==1) return true;
            else return isHappy(sum);
        }
    }
  • 相关阅读:
    CSpinButtonCtrl控件的使用
    JS基础语法
    JS
    层级,hover
    Html&Css
    定位
    制作静态网页
    查看trunk端口
    配置vlan trunk
    js日期的写法,获取girdviw的行数、提示信息、验证数量信息
  • 原文地址:https://www.cnblogs.com/mrpod2g/p/4602728.html
Copyright © 2011-2022 走看看