Yada Number Problem Description: Every positive integer can be expressed by multiplication of prime integers. Duoxida says an integer is a yada number if the total amount of 2,3,5,7,11,13 in its prime factors is even. For instance, 18=2 * 3 * 3 is no…

Yada Number       Time Limit : 2000 MS   Memory Limit : 65536 KB   Yada Number Problem Description: Every positive integer can be expressed by multiplication of prime integers. Duoxida says an integer is a yada number if the total amount of 2,3,5,7,1…

Yada Number Problem Description: Every positive integer can be expressed by multiplication of prime integers. Duoxida says an integer is a yada number if the total amount of 2,3,5,7,11,13 in its prime factors is even. For instance, 18=2 * 3 * 3 is no…

这题被出题人给活活坑了,题目居然理解错了..哎,不想多说. 题意:给两组数,A组为幸运基数,B组为不幸运的基数,问在[low,high]区间内有多少个数:至少被A组中一个数整除,并且不被B中任意一个数整除.|A|<=15. 分析:看到A长度这么小,以及求区间内满足条件的个数问题,容易想到容斥原理,因为不被B中任意一个数整除,所以将B数组所有数取一个最小公倍数LCM,那么就变成了幸运数字都不会被这个LCM整除. 然后枚举子集,实现要将A中元素去除相互整除的情况,比如A = [2,4],这时因为被至…

Number Sequence Time Limit: 10000/3000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Problem Description Given a number sequence b1,b2…bn. Please count how many number sequences a1,a2,...,an satisfy the condition that a1*a2*...*an=b1*…

HDU 4390 题意: 大概就是这样.不翻译了: Given a number sequence b1,b2-bn. Please count how many number sequences a1,a2,...,ansatisfy the condition thata1∗a2∗...∗an=b1∗b2∗-∗bn(ai,bi>1). 思路: 我们能够确定一件事:等号两边由同样数量的质因子组成. 假设ai能够等于1,答案就是把这些质因子分配进n个位置的方案数. 设左边的数字共由x个质因子组成…

题目链接:http://codeforces.com/problemset/problem/245/H 题目大意:给你一个字符串s,对于每次查询,输入为一个数对(i,j),输出s[i..j]之间回文串的个数. 容斥原理: dp[i][j] = dp[i+1][j]+dp[i][j-1]-dp[i+1][j-1]; if( str[i]==str[j] 并且 str[i+1..j-1]是回文串 ) dp[i][j]++; 代码: #include <cstdio> #include <cs…

Problem Description Recently, Mr. Xie learn the concept of happy number. A happy number is a number contain all digit 7 or only 1 digit other than 7. For example, 777 is a happy number because 777 contail all digit 7, 7177 and 87777 both happy number…

Number Busters Time Limit: 1000ms Memory Limit: 262144KB This problem will be judged on CodeForces. Original ID: 382B64-bit integer IO format: %I64d      Java class name: (Any)   Arthur and Alexander are number busters. Today they've got a competitio…

题意: 求小于n (1 ≤ n ≤ 10^8)的数中,与n互质的数的四次方和. 知识点: 差分: 一阶差分: 设  则    为一阶差分. 二阶差分: n阶差分:     且可推出    性质: 1. 2. 差分序列: 给你一列数 a[i][1],a[i][2],a[i][3],a[i][4],a[i][5]…… 那么a[i][j]=a[i-1][j+1]-a[i-1][j], 即后一行是上一行相邻两项的差(第一行除外). 如果给你一个多项式, 比如 f(x)=(x+1)*(x+2)*……*(x…

题意: 给n*m个点(1 ≤ m, n ≤ 1e5),左下角的点为(1,1),右上角的点(n,m),一个人站在(0,0)看这些点.在一条直线上,只能看到最前面的一个点,后面的被档住看不到,求这个人能看到多少个点. 知识点: 容斥原理:(容许) 先不考虑重叠的情况,把包含于某条件中的所有对象的数目先计算出来,(排斥)然后再把计数时重复计算的数目排斥出去,使得计算的结果既无遗漏又无重复. 公式:          奇加偶减 一般求互质个数若用欧拉函数不好解决,则从反面考虑,用容斥. 模板: void…

题目 Source http://acm.hdu.edu.cn/showproblem.php?pid=5838 Description Zhu found a map which is a N∗M rectangular grid.Each cell has a height and there are no two cells which have the same height. But this map is too old to get the clear information,so…

Codeforces Round #258 (Div. 2) Devu and Flowers E. Devu and Flowers time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Devu wants to decorate his garden with flowers. He has purchased n boxes…

网上PoPoQQQ的课件: •题目大意:求第k个无平方因子数 •无平方因子数(Square-Free Number),即分解之后所有质因数的次数都为1的数 •首先二分答案 问题转化为求[1,x]之间有多少个无平方因子数 •根据容斥原理可知 对于sqrt(x)以内所有的质数 有 •  x以内的无平方因子数 •=0个质数乘积的平方的倍数的数的数量(1的倍数) •-每个质数的平方的倍数的数的数量(9的倍数,25的倍数,...) •+每2个质数乘积的平方的倍数的数的数量(36的倍数,100的倍数,...…

How many integers can you find Time Limit: 12000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 7439    Accepted Submission(s): 2200 Problem Description   Now you get a number N, and a M-integers set, you shoul…

GCD Time Limit: 6000/3000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 4272    Accepted Submission(s): 1492 Problem Description Given 5 integers: a, b, c, d, k, you're to find x in a...b, y in c...d that GCD(x, y)…

G - Coprime Time Limit:1000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 5072 Description There are n people standing in a line. Each of them has a unique id number. Now the Ragnarok is coming. We should ch…

E - The Boss on Mars Time Limit:1000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 4059 Description On Mars, there is a huge company called ACM (A huge Company on Mars), and it’s owned by a younger boss. Due…

B - Sky Code Time Limit:1000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u Submit Status Practice POJ 3904 Description Stancu likes space travels but he is a poor software developer and will never be able to buy his own spacecraft. Tha…

The Sports Association of Bangladesh is in great problem with their latest lottery `Jodi laiga Jai'. Thereare so many participants this time that they cannot manage all the numbers. In an urgent meeting theyhave decided that they will ignore some num…

H - Visible Trees Time Limit:1000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 2841 Description There are many trees forming a m * n grid, the grid starts from (1,1). Farmer Sherlock is standing at (0,0) poi…

In most professional sporting events, cheerleaders play a major role in entertaining the spectators. Theirroles are substantial during breaks and prior to start of play. The world cup soccer is no exception.Usually the cheerleaders form a group and p…

F - GCD Time Limit:3000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 1695 Description Given 5 integers: a, b, c, d, k, you're to find x in a...b, y in c...d that GCD(x, y) = k. GCD(x, y) means the greatest c…

1242. Werewolf Time limit: 1.0 secondMemory limit: 64 MB   Knife. Moonlit night. Rotten stump with a short black-handled knife in it. Those who know will understand. Disaster in the village. Werewolf. There are no so many residents in the village. Ma…

http://acm.split.hdu.edu.cn/showproblem.php?pid=4336 Card Collector Special Judge Problem Description   In your childhood, do you crazy for collecting the beautiful cards in the snacks? They said that, for example, if you collect all the 108 people i…

http://acm.hdu.edu.cn/showproblem.php?pid=5768 Lucky7 Problem Description   When ?? was born, seven crows flew in and stopped beside him. In its childhood, ?? had been unfortunately fall into the sea. While it was dying, seven dolphins arched its bod…

幸运数字(number) Time Limit:1000ms   Memory Limit:64MB [题目描述] LYK最近运气很差,例如在NOIP初赛中仅仅考了90分,刚刚卡进复赛,于是它决定使用一些方法来增加自己的运气值.它觉得,通过收集幸运数字可以快速的增加它的RP值.它给幸运数字下了一个定义:如果一个数x能被3整除或被5整除或被7整除,则这个数为幸运数字.于是它想让你帮帮它在L~R中存在多少幸运数字. [输入格式](number.in) 第一行两个数L,R. [输出格式](number…

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…

The Boss on Mars Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1528    Accepted Submission(s): 452 Problem Description On Mars, there is a huge company called ACM (A huge Company on Mars), and…

K. Indivisibility time limit per test 0.5 seconds memory limit per test 64 megabytes input standard input output standard output IT City company developing computer games decided to upgrade its way to reward its employees. Now it looks the following…