the relational database model expression. Decision-free data analysis and decision-making data analysis are two main applications of Rough Set Theory in data analysis. Rough set theory provides the knowledge reduction and core methods to analyze redundant attributes in information systems.If the set B belongs to a and has no redundant attributes, the conciseness of B is a or at, which is marked as red (AT). The intersection of the conciseness in at is called the at core, it is recorded as core
It is known that the two endpoints of a line segment are a (x1, Y1), B (X2, Y2), and the two endpoints of the other line segment are C (X3, Y3), D (X4, y4), to determine whether there is a point between AB and Cd, if any.First Judge d = (y2-y1) (x4-x3)-(y4-y3) (x2-x1 ),If D = 0, the line AB and Cd are parallel or overlapped,If D! = 0, the line AB and CD have the intersection, and the intersection (x0, y0) i
subgraph, And now it still belongs to (or does not belong to) equal subgraph. (Meaning, for the entire graph, if it does not belong to an equal subgraph, it does not belong to an equal subgraph. If it belongs to an equal subgraph, it also belongs to an equal subgraph because it remains unchanged)3. The X end is not in the staggered tree, and the Y end is in the edge (I, j) of the staggered tree. The value of a [I] + B [J] increases. It does not belong to an equal subgraph and does not belong to
The basic idea is to use the principle of rejection.
Hoj 2576 gives a group of numbers x1.... XN and asks how many numbers can be exceeded from 1 to M.
Hoj 2577 gives a group of numbers x1. .. XN and asks how many numbers can be exclusive from 1 to m to the unique number in the group.
2576
X1 + X2 + X3-X1 * x2-X1 * X3-X2 * X3 + X1 * X2 *
Enum)
Enumeration is a set of named Integer constants, which are common in daily life.For example, an enumeration is used to indicate Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, and Saturday of a week.The description of enumeration is similar to the structure and union in the form:Enum enumeration name {Identifier [= integer constant],Identifier [= integer constant],...Identifier [= integer constant],} Enumeration variables;If enumeration is not initialized, that is, when "= integer c
Research discuzx3 source code analysis sequence nbsp; someone on the Internet said that discuz source code analysis from. includecommon. inc. php file, but I downloaded discuz nbsp; x3, and none of them found this file... Nbsp; check whether there is any clue in the file. if you want to analyze discuz nbsp; x3, tell me a rough idea of the order of discuz x3 s
RectanglesTime limit:1000/1000 MS (java/others) Memory limit:32768/32768 K (java/others)Total submission (s): 19110 Accepted Submission (s): 6187Problem Descriptiongiven-rectangles and the coordinates of the points on the diagonals of each rectangle,you has to C Alculate the area of the intersected part of the rectangles. Its sides is parallel to OX and OY.Inputinput the first line of input was 8 positive numbers which indicate the coordinates of four points that must being on EAC H Diagonal. Th
I thought of a method for this question: traverse all vertices in the rectangle area (xmin, ymin, xmax, Ymax) to see if they fall between the two sides.
Then it's TLE.
Query the problem-solving Report on the Internet. Understand the pick theorem: http://en.wikipedia.org/wiki/pick's_theorem
// Pick Theorem// A = I + B/2-1
The area (integer) of a polygon is equal to the number of Integer Points (I) inside the polygon, plus half of the number of Integer Points (B) of the boundary, and then
Calculate the area of a triangle
Time limit: 1000 ms Memory limit: 65536 KB
Number of submissions: 1813 Pass: 622
"topic description"
There is a triangle on the plane, its three vertex coordinates (x1, y1), (x2, y2), (x3, y3), then what is the area of the triangle, accurate to two decimal places.
Enter
Enter only one line, including 6 single-precision floating-point numbers, corresponding to x1, y1, x2, y2,
is no displacement before and after the transformation), and the coefficient i is adjusted to 1, so there is
where p is the scale factor
Write an equation
PX ' = Ax + by (1)
Py ' = Dx + Ey (2)
p = Gx + Hy + 1 (3)
In the Formula 3 elimination 1 and the formula 2 p, you get 2 equations
Ax + by-gxx '-hyx ' = X ' (4)
Dx + ey-gxy '-Hyy ' = Y ' (5)
We assume that the coordinates of the unit square area consisting of point (0,0) (1,0) (0,1) (four) points are mapped to the target plane, respectively
Change of Change:
There are an unlimited number of coins, the value of which is 25, 10, 5 and 1, please write code to calculate n there are several representations.
Given an int n, there are several representations of how to return N. Ensure that n is less than or equal to 100000, in order to prevent overflow, please add the answer mod 1000000007.
Test examples
6
Returns: 2
Dynamic planning
Dp[i][sum] How many ways to make sum with I coins.
Set the face value of a v1,v2,v3,v4 coin
sum = v1*x1+
marked with either 0 or 1. Note that the variable ordering and the distribution of 0 's and 1 ' s on terminal nodes is sufficient to completely describ e an s-tree.As stated earlier, each s-tree represents a Boolean function f. If you have a s-tree and values for the variables x1,x2,..., xn, then it's quite simple-to-find out what f (x1,x2,..., xn) is: Start with the root. Now repeat the Following:if the node that is at was labelled with a variable XI and then depending on whether the value of
variable ordering and the distribution of 0 's and 1 ' s on terminal nodes is sufficient to completely describ e an s-tree.
As stated earlier, each s-tree represents a Boolean function f. If you have a s-tree and values for the variables x1,x2,..., xn, then it's quite simple-to-find out what f (x1,x2,..., xn) Is:start with the root. Now repeat the Following:if the node that is at was labelled with a variable XI and then depending on whether the value of th e variable is 1 or 0 and you go it rig
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The parent function is also called the generating function. The definition is given sequence: A0,A1,A2,....... ak,......, then function g (x) =a0+a1*x+a2*x2+......ak*xk is called sequence A0,A1,A2,....... AK,...... The parent function (that is, the build function).
For example, the generating function for sequence 1,2,3.......N is: G (x) =x+2x2+3x3+........nxn. Click this link: Baidu Encyclopedia
Special when the seq
9 47 0 36 1 0Output2 9 47 5 36 1 8
This question belongs to the maths problem ... It's easy to think of a formula, but it took me a long time to translate it into the equation we needed.The following examples illustrate0 9 47 0 36 1 0
Sum1=0+9+4=13 sum1=7+0+3=10 sum1=6+1+0=7 a[1][1]=x1, a[2][2]=x2, a[3][3]=x3, so there's sum1+x1==sum2+x2= =SUM3+X3==X1+X2+X3
complete.
For tasks that are executed for four hours and then canceled: The tasks are not completed in more than 10 hours.
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After pulling so many items, let's get some dry goods. Why does it take so long to modify the field type?
First, check whether it is caused by hardware resource bottlenecks. The hardware configuration is as follows:
CPU: 48 cores
Memory: 128 GB
IO:
dimension smaller Network monitoring of Sysstat common commands Sar-n DEV-F Network Monitoring statistics Sar-n Nfs-f If the data in this table is greater than 0, the network has errors, which is a more serious situation Evaluating disk read and write performance limits Fio-filename=/tmp/test-direct=1-iodepth 1-thread-rw=randrw-ioengine=psync-bs=16k-size 2g-numjobs=10-runtime=30- group_reporting-name=mytest13
66.80xvdc 0.00 0.00 206.00 1190.00 10.58 148.62 233.56 106.67 70.90 13.83 80.78 0.56 78.40
Found above, two disk Xvdb and XVDC in the wrqm/s above the gap is too large, of course, there are some indicators behind the obvious gap, here is not the detailed explanation iostat output. Just need to be aware that people usually look at the util above, but sometimes light util is not a problem.
So I continued to test with FIO
Tool One: ioPS, a python-written scriptUsage Example: sudo./iops--num_threads 1--time 2/dev/md1Source: http://benjamin-schweizer.de/measuring-disk-io-performance.htmlCode: HTTP://BENJAMIN-SCHWEIZER.DE/FILES/IOPS/IOPS-2011-02-11#!/usr/bin/env python## Copyright (c) 2008-2011 Benjamin Schweizer and others.## Permission to use, copy, modify, and/or D Istribute This software for any# purpose with or without fee are hereby granted, provided that the above# copyright notice And this permission notice
refresh dirty pages.
Innodb_io_capacity: Based on IOPS capability settings, fuionio can be used to set more than 10000.
Innodb_flush_neighbor_pages = 0: For fusionio or SSD, disable this function because random IO is good enough.
Innodb_flush_method = ALL_O_DIRECT: MySQL for the public version can only set database file read and write to DirectIO. For Percona, you can set log and data files to direct read and write. However, I am not sure about the impact of this parameter on innodb_flush_log_a
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