Mathematical knowledge in the first round of noip preliminary round csp-j1 csp-s1 Xinjiang Olympic Games (II)

One 、 Computer Basics

bios

bios_ Baidu Encyclopedia

If a base 7*7=41 The equation holds , that 12*12=?

If a base 7*7=41 The equation holds , that 12*12=?_ Baidu knows

After the computer is powered on, the operating system starts

After the computer is powered on, the operating system starts - *Ronny , - Blog Garden

Computer operating system graphical user interface 38 Annual evolutionary history

https://tech.qq.com/a/20100603/000234.htm

https://www.iteye.com/blog/lhg803-476407

About “32 Bit system supports 4g Memory access ” The understanding of the

About “32 Bit system supports 4g Memory access ” The understanding of the _ForDi A blog whose nickname already exists -CSDN Blog

32 Bit operating system addressing range and maximum memory space supported _ at leisure - A blog with more than one effort -CSDN Blog _32 Addressing range of the root address bus

32 Bit systems can only address 4G Space ,64 Bit is 128G_Data & safety The blog of -CSDN Blog

Major awards and background in computer

CSDN Forum -IT Technology exchange platform

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Two 、 Base number

Tencent classroom

Conversion method between binary and decimal system ( Text course )

Binary system 、 octal 、 Decimal system 、 Conversion between hexadecimals

https://jingyan.baidu.com/article/495ba84109665338b30ede98.html

Talking about C Language memory management 、 Memory leak 、 Stack

https://www.cnblogs.com/youthshouting/p/4280543.html

C Language knowledge arrangement （3）： memory management （ A detailed version ）

C Language knowledge arrangement （3）： memory management （ A detailed version ） - mattran - Blog Garden

Yale open class ： Game theory

Yale open class ： Game theory - Netease public class

Rounding up ?? and Rounding down ?? And rounding

Rounding up ⌈⌉ and Rounding down ⌊⌋ And rounding _ Monkey girl's blog -CSDN Blog _ Rounding mathematical symbols

Programmer's math series （ One ）

Programmer's math series （ One ）_Alex-Zhang The blog of -CSDN Blog _ Math for programmers 1

Math for programmers （ One ） - Alex Zhang Personal space - OSCHINA - Chinese open source technology exchange community

3、 ... and 、 Permutation and combination

1. Carter LAN number

A preliminary study of Cartland numbers - An uncle - Blog Garden

Carter LAN number Catalan Count ( ACM number theory Combine ) - ACM___________________________ - C++ Blog

Carter LAN number - SuperChan - Blog Garden

Carter LAN number - SuperChan - Blog Garden

Catalan Count —— Carter LAN number - Invite the moon to pour alone - Blog Garden

catalan--- Carter LAN number （ Summary ） - Gong Xijun - Blog Garden

【 Knowledge summary 】 Carter LAN number (Catalan Number) Derivation of formula - Inspector_Javert - Blog Garden

n Put an element on the stack , How many kinds of stack order are there ？ - jiayouwyhit - Blog Garden

Catalan Count —— Carter LAN number _hackbuteer1 The blog of -CSDN Blog _catalan Count

Carter LAN number （ It seems very useful to say ）_Coco_T_ The blog of -CSDN Blog _ Cartland number calculation formula

Cartland number in combinatorics _LB_ Moheyanqi's blog -CSDN Blog

n Put an element on the stack , How many kinds of stack order are there （ The formula ）_ Blog of the national second-class remnant sequencer -CSDN Blog _ Stack order formula

N The number is put on the stack in turn , How many kinds of stack order _shikelang_pp The blog of -CSDN Blog _ Stack in turn

2、 Arrange and combine

seek 2n The maximum and minimum of the number , The least number of comparisons is ？

seek n The maximum and minimum of the number , The least number of comparisons is ？__ Cattle from

A permutation problem

m It's the same ball , Put it in n In a different bag . ask ： How many ways can a play ？ Give your analysis method . thank you ！

A permutation problem m It's the same ball , Put it in n In a different bag ： One has Love to ask intellectual

nail 、 B 、 C 3 Students take elective courses , from 4 In the course of , A elective course 2 door , B 、 C each elective course 3 door , There are different elective programs ______ Kind of ．（ Answer with numbers ）

nail 、 B 、 C 3 Students take elective courses , from 4 In the course of , A elective course 2 door , B 、 C each elective course 3 door , There are different elective programs ______ Kind of ．（ Answer with numbers ）- High school math -n Multiple questions

take 5 Sequence of numbers , Whatever the original order , At least you can

Sina blog

take m Put all the same balls in n There are several ways to put them in the same box

take m Put all the same balls in n There are several ways to put them in the same box _wuyingzhiyi The blog of -CSDN Blog _ Put the same ball in the same box

NOIP Possible permutations and combinations

NOIP Possible permutations and combinations _WWWengine The blog of -CSDN Blog

Combinatorial mathematics —— Number of permutations

Combinatorial mathematics —— Number of permutations _Alex_McAvoy The blog of -CSDN Blog _ Number of permutations

3、 Combinatorial mathematics

Combinatorial mathematics Beijing Normal University Zhangxiuping self-taught video NOIP_mrcrack The blog of -CSDN Blog

【 knowledge 】 Combinatorial mathematics _Starlight_Glimmer The blog of -CSDN Blog _ Combinatorial mathematics csdn

Combinatorial mathematics -- Wrong way _ The color of sunshine blog -CSDN Blog

Combinatorial mathematics _ Harbin Engineering University _ University of China MOOC( MOOC )

Permutation and combination "n Put a ball in m Boxes m" problem summary

Permutation and combination "n Put a ball in m Boxes m" problem summary _ Xiaoyao, Qi's blog -CSDN Blog _n Put a ball in m A box theorem

from 0,1,2,3,4,5 These six numbers ．

（1） How many four digits of non repeating numbers can be formed ？

（2） How many non repeating numbers can be formed and 25 Four digits of integer division ？

（3） A four digit median ratio that makes up a non repeating number 4032 How many big numbers are there ．

from 0,1,2,3,4,5 These six numbers ．（1） How many four digits of non repeating numbers can be formed ？（2） How many non repeating numbers can be formed and 25 Four digits of integer division ？（3） A four digit median ratio that makes up a non repeating number 4032 How many big numbers are there ．- High school math -n Multiple questions

hold 8 Give the same apple to 3 On the same plate

hold 8 Give the same apple to 3 On the same plate _ Baidu knows

21 This book , Number from 1 To 21, Choose from 4 Ben , There are several choices in which the numbers of each two books are not adjacent ?

21 This book , Number from 1 To 21, Choose from 4 Ben , There are several choices in which the numbers of each two books are not adjacent ?_ Baidu knows

take 7 Give a place to 4 Different classes , Some classes are allowed to have no places , There are several options ？

take 7 Give a place to 4 Different classes , Some classes are allowed to have no places , There are several options ？_ Baidu knows

There is... In the room 4 personal , At least 2 What is the probability that an individual's birthday is in the same month ？

There is... In the room 4 personal , At least 2 What is the probability that an individual's birthday is in the same month ？_ Baidu knows

Rearrange 1234 So that every number is not in its original position , Altogether ___________ To arrange

Rearrange 1234 So that every number is not in its original position , Altogether ___________ To arrange _ Baidu knows

hold 7 Put an indistinguishable apple in 3 On a different plate ( An empty disk is allowed ), How many different ways are there （）

Baidu library

There are... In the room 4 personal , Ask the probability that at least two people have the same birthday in the same month ？

Baidu library

16． take 5 Sequence of numbers , Whatever the original order , At least they can pass （ ） Compare it to , Finish sorting from small to large .A.6 B.7 C.8 D.9

16． take 5 Sequence of numbers , Whatever the original order , At least they can pass （ ） Compare it to , Finish sorting from small to large .A.6 B.7 C.8 D.9_ Homework help

hold n A different ball , Put it in m In a different bag , At least each bag has 1 A ball , How many ways to put it ?

hold n A different ball , Put it in m In a different bag , At least each bag has 1 A ball , How many ways to put it ? hold n A different ball , Put it in m In a different bag , At least each bag has 1 A ball , How many ways to put it ? For example, when n=3 m=2 when {1} {2,3}{2} {1,3}{3} {1,2}{2,3_ Homework help

Yes 10 Three good students , Assigned to six classes , At least one in each class , There are several divisions ?

A detailed description is required , It is better to have multiple solutions . The answer for 126.

Yes 10 Three good students , Assigned to six classes , At least one in each class , There are several divisions ? A detailed description is required , It is better to have multiple solutions . The answer for 126._ Homework help

Yes 10 Three good students , Assigned to 6 A class , At least per shift 1 I saw a solution like this 6 Classes are in the middle , At least per shift 1 Places , Is to ensure that every shift 1 On a quota basis , And then randomly put the rest 4 Arrange the number of seats . therefore , The assignment scheme of this question _ Homework help

hold 7 Put the same apple in 3 On the same plate , The plate can be empty , How many ways do you put it in the middle

hold 7 Put the same apple in 3 On the same plate , The plate can be empty , How many ways do you put it in the middle ,（ notes ： Not to list , And as ：1,1,5, and 1,5,1, As the same way ） Please give me some suggestions , It's better to write a formula , Thank you in advance !_ Homework help

Why is this question 5!*4!=2880

Why is this question 5!*4!=2880 stay NOI period , To welcome the contestants from all over the country , A grand dinner was held . At table 18 , There are five mainland athletes and five Hong Kong and Macao athletes eating together . In order to enhance communication , They decided to do it every other time , That is, each big _ Homework help

How many ways

Will be indistinguishable 7 Three apples on three identical plates , Some plates are allowed to remain empty ． How many different ways are there ？

How many methods will be indistinguishable 7 Three apples on three identical plates , Some plates are allowed to remain empty ． How many different ways are there ？_ Homework help

use 1,1,2,4,8,8 These numbers , Combine into four digits , How many combinations can there be ?

use 1,1,2,4,8,8 These numbers , Combine into four digits , How many combinations can there be ?_ Homework help

data structure : Ruoshan S=‘software’, The number of substrings is （37）. Is there a calculation formula ?

data structure : Ruoshan S=‘software’, The number of substrings is （37）. Is there a calculation formula ?_ Homework help

4. Sudoku question

How to play Sudoku , Simple problem solution analysis

https://jingyan.baidu.com/article/90bc8fc8a9c851f652640c59.html

How to solve Sudoku

https://jingyan.baidu.com/article/fdffd1f8325b32f3e98ca1dd.html

Sudoku question

Sudoku question _sdljtyk The blog of -CSDN Blog

【 Algorithm analysis 】 Backtracking for Sudoku （ squared paper for practicing calligraphy ） Algorithm

【 Algorithm analysis 】 Backtracking for Sudoku （ squared paper for practicing calligraphy ） Algorithm _Ezio_AC The blog of -CSDN Blog _ Backtracking for Sudoku

backtracking 、 Sudoku and N Order reachability problem

backtracking 、 Sudoku and N Order reachability problem - Seven centimeters of light and shadow - Blog Garden

5. Minimum steps

【 example 8.3】 Minimum steps

【 example 8.3】 Minimum steps - Ed_Sheeran - Blog Garden

1330：【 example 8.3】 Minimum steps

1330：【 example 8.3】 Minimum steps _PX-C The blog of -CSDN Blog

bfs Minimum steps

bfs Minimum steps _pxlsdz The blog of -CSDN Blog _ Minimum steps

1330：【 example 8.3】 Minimum steps _PX-C The blog of -CSDN Blog