/* 枚举素数幂p 然后求k^p<=n 的 k的个数 因为 k^p1*p2==k^p2*p1,所以这两种情况是多算的,所以要进行容斥 减去两个质数幂相乘的,再加上三个质数幂相乘的 因为2*3*5*7>60,所以最多容斥两次就可以 枚举pi最为起点进行深搜,只搜比pi大的 */ #include<bits/stdc++.h> using namespace std; #define ll long long ,,,,,,,,,,,,,,,,}; ll ans,n; //素数下标pos…

BZOJ_2393_Cirno的完美算数教室&&BZOJ_1853_[Scoi2010]幸运数字 _深搜+容斥原理 题意: ~Cirno发现了一种baka数,这种数呢~只含有2和⑨两种数字~~ 现在Cirno想知道~一个区间中~~有多少个数能被baka数整除 分析: 基本思路是找到1e10以内所有的baka数,如果a[i]%a[j]==0则把a[i]删掉 每个方案的lcm的贡献是r/lcm-(l-1)/lcm,深搜每一种情况,用容斥原理确定正负 考虑优化,从大到小枚举baka数,当lcm大…

2393: Cirno的完美算数教室 Time Limit: 10 Sec  Memory Limit: 128 MBSubmit: 287  Solved: 175[Submit][Status][Discuss] Description ~Cirno发现了一种baka数,这种数呢~只含有2和⑨两种数字~~ 现在Cirno想知道~一个区间中~~有多少个数能被baka数整除~ 但是Cirno这么天才的妖精才不屑去数啦 只能依靠聪明的你咯.     Input 一行正整数L R  ( 1 < L…

1853: [Scoi2010]幸运数字 Time Limit: 2 Sec  Memory Limit: 64 MBSubmit: 1774  Solved: 644[Submit][Status][Discuss] Description 在中国,很多人都把6和8视为是幸运数字!lxhgww也这样认为,于是他定义自己的“幸运号码”是十进制表示中只包含数字6和8的那些号码,比如68,666,888都是“幸运号码”!但是这种“幸运号码”总是太少了,比如在[1,100]的区间内就只有6个(6,8,…

这个题我看了,都是推荐的神马双向广搜,难道这个深搜你们都木有发现?还是特意留个机会给我装逼? Open the Lock Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 3014    Accepted Submission(s): 1323 Problem Description Now an emergent task for you…

利用TreeView控件加载文件,必须遍历处所有的文件和文件夹. 深搜算法用到了递归. using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows…

题目链接 https://acm.bnu.edu.cn/v3/problem_show.php?pid=52310 problem description Define the depth of a node in a rooted tree by applying the following rules recursively: • The depth of a root node is 0. • The depths of child nodes whose parents are with…

题目链接 https://acm.bnu.edu.cn/v3/problem_show.php?pid=52305 problem  description In ICPCCamp, there are n cities and (n−1) (bidirectional) roads between cities. The i-th road is between the ai-th and bi-th cities. It is guaranteed that cities are conne…

题目链接:HDU 5355 http://acm.split.hdu.edu.cn/showproblem.php?pid=5355 Problem Description There are m soda and today is their birthday. The 1-st soda has prepared n cakes with size 1,2,…,n. Now 1-st soda wants to divide the cakes into m parts so that th…

POJ 2676 Sudoku Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 17627   Accepted: 8538   Special Judge Description Sudoku is a very simple task. A square table with 9 rows and 9 columns is divided to 9 smaller squares 3x3 as shown on the…