主题链接:http://acm.hdu.edu.cn/showproblem.php? pid=5062 Problem Description A positive integer x can represent as (a1a2-akak-a2a1)10 or (a1a2-ak−1akak−1-a2a1)10 of a 10-based notational system, we always call x is a Palindrome Number. If it satisfies 0<…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5062 题目意思:给出 N,找出 1 - 10^N 中满足 Beautiful Palindrome Numbers (BPN)的数量有多少. 满足 BPN 的条件有两个:(1)回文串   (2)对称的部分从左到右递增排放. (1)版本 1 (比较麻烦,建议看版本2)        46ms #include <iostream> #include <cstdio> #include &…

题意:将10^0-10^6之间属于  "Beautiful Palindrome Number" 的数个数打印出来,所谓 "Beautiful Palindrome Number" 是指一中回文串数字,比如123321或者12321,类似于这种的数........ 分析:代码我是直接打表出来的,因为T<=7,N<=6,数据不大..... AC代码: #include <iostream> using namespace std; int ma…

Beautiful Palindrome Number Time Limit: 3000/1500 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1067    Accepted Submission(s): 691 Problem Description A positive integer x can represent as (a1a2…akak…a2a1)10 or (a…

文章转自http://blog.163.com/hljmdjlln@126/blog/static/5473620620120412525181/ 做LC上的题"Palindrome number"时翻到此文章,经过少量修改后如下. 回文数是数学界中的一种有趣的现象.比如121就是一个回文数.回文数的数字互相对应,从中间一个任意一位数字起,左右每隔一个的数字都相等.回文数有许多神奇的规律和奥秘.主要分为读数回文数.平方回文数.乘积回文数以及倒乘回文数. 一.读数回文数 [解释]读数回文…

hdu 6216 A Cubic number and A Cubic Number[数学] 题意:判断一个素数是否是两个立方数之差,就是验差分.. 题解:只有相邻两立方数之差才可能,,因为x^3-y^3=(x-y)(x^2+xy+y^2),看(x-y),就能很快想到不相邻的立方数之差是不可能是素数的:),,然后把y=x+1代入,得:p=3x^2+3x+1,所以可得判断条件为:①p-1必须能被3整除:②(p-1)/3必须能表示为两个相邻整数之积. #include<iostream> #inc…

文章转自http://blog.163.com/hljmdjlln@126/blog/static/5473620620120412525181/ 做LC上的题"Palindrome number"时翻到此文章,经过少量修改后如下. 回文数是数学界中的一种有趣的现象.比如121就是一个回文数.回文数的数字互相对应,从中间一个任意一位数字起,左右每隔一个的数字都相等.回文数有许多神奇的规律和奥秘.主要分为读数回文数.平方回文数.乘积回文数以及倒乘回文数. 一.读数回文数 [解释]读数回文…

Reverse Integer Reverse digits of an integer. Example1: x =  123, return  321 Example2: x = -123, return -321 click to show spoilers. Have you thought about this? Here are some good questions to ask before coding. Bonus points for you if you have alr…

/* Determine whether an integer is a palindrome. Do this without extra space. click to show spoilers. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of converting the integer to string, note the restriction of using…

9. Palindrome Number Total Accepted: 136330 Total Submissions: 418995 Difficulty: Easy Determine whether an integer is a palindrome. Do this without extra space. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of conv…