很有意思的一个数论题. 是这样的,给你一个数数组a[i],其中给出的每一个数字和要求的数字方位都是[1,m],现在问你根据a[]构造一个b[],且a和b中间的不相等的元素的个数恰好有k个. 现在问你gcd(b[])分别为1,2,……,m的个数分别有多少种可能情况. 额...是这样来考虑的.——————容斥原理. 有点像素数筛选,但是复杂一点. 对于个数我们需要从大到小来求解(这里的缘由自己想象就知道了) 假设当前我需要求解有多少个情况满足gcd(b[])=x,那么显然b中的所有的数都必须是x的倍…

oracle创建序列化: CREATE SEQUENCE seq_itv_collection            INCREMENT BY 1  -- 每次加几个              START WITH 1399       -- 从1开始计数              NOMAXVALUE        -- 不设置最大值              NOCYCLE               -- 一直累加,不循环              CACHE 10; oracle修改序列…

功能:备份存储过程,视图,函数触发器,Sequence序列号等准备工作:--1.创建文件夹 :'E:/OracleBackUp/ProcBack';--文本存放的路径--2.执行:create or replace directory MyProcBakPath as 'E:/OracleBackUp/ProcBack';--3.赋权限:sqlplus /nologconn user/pswd as sysdbagrant select on DBA_OBJECTS to user;--4.创建…

环境:Oracle 11.2.0.4 DG 故障现象: 客户在备库告警日志中发现GAP sequence提示信息: Mon Nov 21 09:53:29 2016 Media Recovery Waiting for thread 1 sequence 12034 Fetching gap sequence in thread 1, gap sequence 12034-12078 Mon Nov 21 09:55:20 2016 FAL[client]: Failed to request…

The set [1,2,3,-,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order,We get the following sequence (ie, for n = 3): "123" "132" "213" "231" "312" "3…

Check whether the original sequence org can be uniquely reconstructed from the sequences in seqs. The org sequence is a permutation of the integers from 1 to n, with 1 ≤ n ≤ 104. Reconstruction means building a shortest common supersequence of the se…

Given a binary tree, find the length of the longest consecutive sequence path. The path refers to any sequence of nodes from some starting node to any node in the tree along the parent-child connections. The longest consecutive path need to be from p…

Given an array of numbers, verify whether it is the correct preorder traversal sequence of a binary search tree. You may assume each number in the sequence is unique. Follow up: Could you do it using only constant space complexity? 这道题让给了我们一个一维数组,让我们…

Given an unsorted array of integers, find the length of the longest consecutive elements sequence. For example, Given [100, 4, 200, 1, 3, 2], The longest consecutive elements sequence is [1, 2, 3, 4]. Return its length: 4. Your algorithm should run i…

The set [1,2,3,…,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order,We get the following sequence (ie, for n = 3): "123" "132" "213" "231" "312" "3…