Exclusive or 题目链接: http://acm.hust.edu.cn/vjudge/contest/121336#problem/J Description Given n, find the value of Note: ♁ denotes bitwise exclusive-or. Input The input consists of several tests. For each tests: A single integer n (2≤n<10^500). Output…

题意很简单, 就是给个n, 算下面这个式子的值. $\sum\limits_{i=1}^{n-1} i \otimes (n-i)$ 重点是n的范围:2≤n<10500 比赛的时候 OEIS一下得到了一个公式: $a_0=a_1=a_2=0$; n为偶数 : $2 \times a_{\frac{n}{2}}+2 \times a_{\frac{n}{2}-1}+4\times (\frac{n}{2}-1) $ n为奇数 : $4\times a_{\frac{n-1}{2}}+6\times…

Exclusive or Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others) Total Submission(s): 327    Accepted Submission(s): 137 Problem Description Given n, find the value of  Note: ⊕ denotes bitwise exclusive-or.   Input T…

题意: 定义 \[f(n)=\sum\limits_{i=1}^{n-1}(i\oplus (n-i))\] 求\(f(n),n \leq 10^{500}\) 分析: 这个数列对应OEIS的A006582 先上公式: \[f(n)=\left\{\begin{matrix} 4f(k)+6k,n=2k+1\\ 2f(k)+2f(k-1)+4k-4,n=2k \end{matrix}\right.\] 递推的思路就是虽然不知道两个数的异或值,但是如果知道这两个数的奇偶性那么结果的奇偶性也就知道了…

== oeis: 点击打开链接 瞎了,x.mod(BigInteger.ValueOf(2)).equal( BigInteger.ValueOf(1)) 写成了 x.mod(BigInteger.ValueOf(2)).equal( 1 ) T^T100块没了.. . import java.math.*; import java.util.*; import static java.lang.System.out; import java.io.*; public class Main {…

HDU 4911 Inversion 考点:归并排序 思路:这题呀比赛的时候忘了知道能够用归并排序算出逆序数,可是忘了归并排序的实质了.然后不会做-- 由于看到题上说是相邻的两个数才干交换的时候.感觉归并排序好像不是得要相邻的呀.然后就这样晕--刚才又一次看了才发现,归并就是相邻的交换的,正好是用来求逆序数的,唉--真的是做这个归并排序比赛就来了--真好! #include<iostream> #include<cstdio> #include<cstring> #in…

Binary Tree Traversals Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 4330    Accepted Submission(s): 1970 Problem Description A binary tree is a finite set of vertices that is either empty or…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4069 Problem Description Today we play a squiggly sudoku, The objective is to fill a 9*9 grid with digits so that each column, each row, and each of the nine Connecting-sub-grids that compose the grid co…

主题链接:http://acm.hdu.edu.cn/showproblem.php?pid=4915 Parenthese sequence Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others) Total Submission(s): 172    Accepted Submission(s): 69 Problem Description bobo found an anc…

Boring String Problem Time Limit: 6000/3000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 1848    Accepted Submission(s): 492 Problem Description In this problem, you are given a string s and q queries. For each qu…

Binary Tree Traversals Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 2442    Accepted Submission(s): 1063 Problem Description A binary tree is a finite set of vertices that is either empty or…

zxa and xor 题目连接: http://acm.hdu.edu.cn/showproblem.php?pid=5683 Description zxa had a great interest in exclusive disjunction(i.e. XOR) recently, therefore he took out a non-negative integer sequence a1,a2,⋯,an of length n. zxa thought only doing th…

Binary Tree Traversals Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 9283    Accepted Submission(s): 4193 Problem Description A binary tree is a finite set of vertices that is either empty or…

题链;http://acm.hdu.edu.cn/showproblem.php?pid=1710 Binary Tree Traversals Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 4205    Accepted Submission(s): 1904 Problem Description A binary tree i…

Saving HDU Time Limit: 3000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 7194    Accepted Submission(s): 3345 Problem Description 话说上回讲到海东集团面临内外交困,公司的元老也只剩下XHD夫妇二人了.显然,作为多年拼搏的商人,XHD不会坐以待毙的.  一天,当他正在苦思冥想解困良策的…

http://acm.hdu.edu.cn/showproblem.php?pid=3037 Lucas定理模板. 现在才写,noip滚粗前兆QAQ #include<cstdio> #include<cstring> #include<algorithm> using namespace std; typedef long long ll; int jc[100003]; int p; int ipow(int x, int b) { ll t = 1, w = x;…

http://acm.hdu.edu.cn/showproblem.php?pid=4859 题目大意: 在一个矩形周围都是海,这个矩形中有陆地,深海和浅海.浅海是可以填成陆地的. 求最多有多少条方格线满足两侧分别是海洋和陆地 这道题很神 首先考虑一下,什么情况下能够对答案做出贡献 就是相邻的两块不一样的时候 这样我们可以建立最小割模型,可是都说是最小割了 无法求出最大的不相同的东西 所以我们考虑转化,用总的配对数目 - 最小的相同的对数 至于最小的相同的对数怎么算呢? 我们考虑这样的构造方法:…

Special equations Time Limit:1000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 4569 Description Let f(x) = a nx n +...+ a 1x +a 0, in which a i (0 <= i <= n) are all known integers. We call f(x) 0 (mod…

The kth great number Time Limit:1000MS     Memory Limit:65768KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 4006 Description Xiao Ming and Xiao Bao are playing a simple Numbers game. In a round Xiao Ming can choose to write down a nu…

How many integers can you find Time Limit:5000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 1796 Description   Now you get a number N, and a M-integers set, you should find out how many integers which are sm…

(转)http://blog.csdn.net/u013081425/article/details/39240021 http://acm.hdu.edu.cn/showproblem.php?pid=4418 读了一遍题后大体明白意思,但有些细节不太确定.就是当它处在i点处,它有1~m步可以走,但他走的方向不确定呢.后来想想这个方向是确定的,就是他走到i点的方向,它会继续朝着这个方向走,直到转向回头. 首先要解决的一个问题是处在i点处,它下一步该到哪个点.为了解决方向不确定的问题,将n个点转…

1.题目地址: http://acm.hdu.edu.cn/showproblem.php?pid=3791 2.参考解题 http://blog.csdn.net/u013447865/article/details/22569639 这个题目本身简单,我的想法也很easy,但是发生在测试上,我把memset的参数搞错了,第三个是sizeof(a), 比如说int a[10],第三个参数应该是sizeof(10),也就是40,而我传的是10,导致后面的测试,都是答案错误,也就是后面的数据,初始…

problem:http://acm.hdu.edu.cn/showproblem.php?pid=4329 题意:模拟  a.     p(r)=   R'/i   rel(r)=(1||0)  R是前n次输入有关URL的个数  R'是后n次已经输入有关URL的个数 b.   另加:输入 istringstream #include<iostream> #include<sstream> //istringstream 必须包含这个头文件 #include<string&g…

http://acm.hdu.edu.cn/showproblem.php?pid=2586 题意:求最近祖先节点的权值和 思路:LCA Tarjan算法 #include <stdio.h> #include <string.h> #define maxn 40005 ],pos,dist[maxn],f[maxn]; bool vis[maxn]; struct Edge{ int to,val,next; }edge[maxn*]; void add(int u,int v,…

http://acm.hdu.edu.cn/showproblem.php?pid=1429 一个广搜的简单题吧,不过有意思的事这个题目用到了位运算,还有就是很恶心的MLE #include <stdio.h> #include <string.h> #include <queue> using namespace std; int m,n,t; ][]; ][][<<]; ][] = {-,,,,,-,,}; struct note{ int x,y,st…

http://acm.hdu.edu.cn/showproblem.php?pid=1878 题意:就是判断这个图是不是一个欧拉回路的一个题, 思路:我觉得这个题可以用并查集判环加上判断每个点的度就行了 #include <stdio.h> #include <string.h> #include <queue> using namespace std; ]; ]; int Find(int x) { int _x=x,_b; while( _x != belg[ _x…

hdu5901题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5901 code vs 3223题目链接:http://codevs.cn/problem/3223/ 思路:主要是用了一个Meisell-Lehmer算法模板,复杂度O(n^(2/3)).讲道理,我不是很懂(瞎说什么大实话....),下面输出请自己改 #include<bits/stdc++.h> using namespace std; typedef long long LL;…

链接:http://acm.split.hdu.edu.cn/showproblem.php?pid=2191 思路:多重背包模板题 #include <stdio.h> #include <stdlib.h> #include <string.h> #include <math.h> #include <algorithm> using namespace std; int money,type; ],weigh[],num[],dp[]; i…

链接:http://acm.hdu.edu.cn/showproblem.php?pid=5384 思路:没学自动机时以为是道KMP然后就tle了好几把,AC自动机模板题 #include<cstdio> #include<iostream> #include<algorithm> #include<math.h> #include<string.h> #include<vector> #include<queue> #i…

链接:http://acm.hdu.edu.cn/showproblem.php?pid=2222 思路:裸AC自动机,直接贴代码做模板 #include<stdio.h> #include<string.h> #include<malloc.h> #include<queue> using namespace std; +]; struct node { int count; ]; struct node *fail; void init() { int…