Ce cours concerne les arbres, structure de données organisant les données de manière hiérarchique dans de nœuds reliés entre eux par une relation parent-enfant. Le cours présente les arbres généraux et ensuite les arbres binaires, où chaque nœud possède 0 ou 2 enfants. Enfin, le cours termine en présentant des algorithmes de recherche et en particulier l'arbre binaire de recherche.
Frequent Pattern Growth Algorithm is a tree model to find frequent patterns without candidate generation. FP method works faster than the Apriori algorithm.
A graph G is composed of vertices V connected by edges E. It can be represented using an adjacency matrix or adjacency lists. Graph search algorithms like depth-first search (DFS) and breadth-first search (BFS) are used to traverse the graph and find paths between vertices. DFS recursively explores edges until reaching the end of a branch before backtracking, while BFS explores all neighbors at each level before moving to the next.
Fun with Lambdas: C++14 Style (part 1)Sumant Tambe
If virtual functions in C++ imply design patterns, then C++ lambdas imply what? What does it really mean to have lambdas in C++? Frankly, I don't know but I've a hunch: It's BIG.
Just like virtual functions open doors to the OO paradigm, lambdas open doors to a different paradigm--the functional paradigm. This talk is not a praise of functional programming or some elusive lambda-based library. (Although, I'll mention one briefly that tops my list these days.) Instead, the goal is to have fun while working our way through some mind-bending examples of C++14 lambdas. Beware, your brain will hurt! Bring your laptop and code the examples right along because that may be the fastest way to answer the quiz.
Ce chapitre est destiné pour les étudiants de la 1ère année Master MMCSI, Semestre 1. Il traite les points suivants:
Définition des arbres binaires
Arbres binaires particuliers
Implantation d’un arbre binaire
Notion de parcours
Les primitives sur les arbres binaires
Les autres fonctions sur les arbres binaires
The document discusses SQL pattern matching using regular expressions. It provides an introduction to regular expression concepts and functions in Oracle for pattern matching like REGEXP_LIKE, REGEXP_SUBSTR, etc. It then describes how to go beyond the capabilities of these functions to retrieve related rows using SQL pattern matching with clauses like MATCH_RECOGNIZE, PATTERN, DEFINE, MEASURES and examples like identifying successive login failures and sessionization of clickstream data.
Network security is main concern now-a-days and
Snort is one of the advanced techniques that is used to tackle
rising security threats over the internet. Snort is kind of Network
Intrusion Detection System that allows user to write their own
rules to detect different attacks over the network on the basis of
their signatures and further gives freedom to users to handle
these attacks in different ways. MIT-DARPA 1999 dataset (which
consists of both normal and abnormal traffic) is used for
evaluation of Snort in this paper. This evaluation is done with the
help of the proposed detection rules. In this paper we have
detected all kinds of attacks i.e. DOS, U2R, R2L, Probe and data
attacks. These proposed rules results are further compared to the
Detection Scoring Truth of DARPA 1999 dataset.
Ce cours concerne les arbres, structure de données organisant les données de manière hiérarchique dans de nœuds reliés entre eux par une relation parent-enfant. Le cours présente les arbres généraux et ensuite les arbres binaires, où chaque nœud possède 0 ou 2 enfants. Enfin, le cours termine en présentant des algorithmes de recherche et en particulier l'arbre binaire de recherche.
Frequent Pattern Growth Algorithm is a tree model to find frequent patterns without candidate generation. FP method works faster than the Apriori algorithm.
A graph G is composed of vertices V connected by edges E. It can be represented using an adjacency matrix or adjacency lists. Graph search algorithms like depth-first search (DFS) and breadth-first search (BFS) are used to traverse the graph and find paths between vertices. DFS recursively explores edges until reaching the end of a branch before backtracking, while BFS explores all neighbors at each level before moving to the next.
Fun with Lambdas: C++14 Style (part 1)Sumant Tambe
If virtual functions in C++ imply design patterns, then C++ lambdas imply what? What does it really mean to have lambdas in C++? Frankly, I don't know but I've a hunch: It's BIG.
Just like virtual functions open doors to the OO paradigm, lambdas open doors to a different paradigm--the functional paradigm. This talk is not a praise of functional programming or some elusive lambda-based library. (Although, I'll mention one briefly that tops my list these days.) Instead, the goal is to have fun while working our way through some mind-bending examples of C++14 lambdas. Beware, your brain will hurt! Bring your laptop and code the examples right along because that may be the fastest way to answer the quiz.
Ce chapitre est destiné pour les étudiants de la 1ère année Master MMCSI, Semestre 1. Il traite les points suivants:
Définition des arbres binaires
Arbres binaires particuliers
Implantation d’un arbre binaire
Notion de parcours
Les primitives sur les arbres binaires
Les autres fonctions sur les arbres binaires
The document discusses SQL pattern matching using regular expressions. It provides an introduction to regular expression concepts and functions in Oracle for pattern matching like REGEXP_LIKE, REGEXP_SUBSTR, etc. It then describes how to go beyond the capabilities of these functions to retrieve related rows using SQL pattern matching with clauses like MATCH_RECOGNIZE, PATTERN, DEFINE, MEASURES and examples like identifying successive login failures and sessionization of clickstream data.
Network security is main concern now-a-days and
Snort is one of the advanced techniques that is used to tackle
rising security threats over the internet. Snort is kind of Network
Intrusion Detection System that allows user to write their own
rules to detect different attacks over the network on the basis of
their signatures and further gives freedom to users to handle
these attacks in different ways. MIT-DARPA 1999 dataset (which
consists of both normal and abnormal traffic) is used for
evaluation of Snort in this paper. This evaluation is done with the
help of the proposed detection rules. In this paper we have
detected all kinds of attacks i.e. DOS, U2R, R2L, Probe and data
attacks. These proposed rules results are further compared to the
Detection Scoring Truth of DARPA 1999 dataset.
Java and Spring Data JPA: Easy SQL Data Access
Abstract
Presenter: Miya W. Longwe, MBA, MSE, Tech Lead, Staples, Inc, Framingham MA 01702
Accessing data repositories in various applications programming languages typically involves writing of tedious boilerplate lines of code. Some application development frameworks such as Spring have tried to make the experience more succinct by providing abstraction layers such as HibernateTemplate and JdbcTemplate, etc. Despite these APIs, the developers still spend a lot time writing repetitive code than concentrating on implementing business requirements. Developers at Spring, led by Oliver Gierke, introduced Spring Data JPA which “aims to significantly improve the implementation of data access layers by reducing the effort to the amount that's actually needed. As a developer you write your repository interfaces, including custom finder methods, and Spring will provide the implementation automatically”.
Spring Data JPA provides a powerful, out-of-the-box alternative to creating your own DAO framework. You declare custom repository operations on an interface, and the framework generates dynamic implementations (not code generation) automatically, based on conventions around method names. As part of the presentation, we'll also review a demo to look at Spring Java configuration (as opposed to XML configuration), and investigate the @Profile annotation – configuration details which may make life a bit easier in various ways when setting up unit testing of our repository classes, using out-of-the-box alternative to creating DAO framework, how to create custom repositories, pagination and support for custom queries among other features.
Presenter's Bio
Miya W. Longwe is a Senior Software Engineer and Tech Lead at Staples, Inc. where he is currently working on an initiative to re-platform the company’s ecommerce architecture to offer platform-driven, modular products that can be quickly customized, enhanced, and branded as needed.
Miya has been a software professional since 1997. His 16 years software development career includes working for large companies to small startups, building solutions for enterprises and consumers, working with a broad range of technologies.
Miya Longwe is a hands-on java developer. He believes that in order to be a relevant and effective software developer one needs to remain a deeply knowledgeable, up-to-date, and productive software developer. His research interests include model-driven engineering, domain specific languages, test driven development and project risk management.
Miya graduated from the University of Malawi (Lilongwe, Malawi) and has an MBA from the University of Wales Cardiff Business School (Wales, UK) and a Masters in Software Engineering from Brandeis University (MA, USA).
Occasionally, Miya can be spotted fishing the banks of the south shore (MA) with his two boys, William and Daniel.
The document is a lecture on the SQL language given at Trinity College. It introduces SQL as the standard language for relational databases and describes it as declarative, meaning the user specifies the desired results without specifying how to retrieve them. It then discusses some basic SQL statements like CREATE TABLE to define the structure of tables and import data types for attributes.
Sparse matrices are matrices that have relatively few nonzero elements, allowing for specialized storage techniques. They occur often in applications involving partial differential equations, text analysis, optimization, and network modeling. A sparse matrix example is presented with nonzero elements only in certain locations. Key sparse matrix types include triangular, banded, diagonal, and tridiagonal matrices.
DESIGNING IT BLUEPRINT WITH TOGAF FOR INFORMATION TECHNOLOGY DEVELOPMENTIAEME Publication
The use of information technology that is aligned with the company's goals will be
achieved if supported by a good governance planning system. Therefore, to develop
information technology can use the Enterprise Architecture approach as a guideline
or blueprint in the development of information technology. The XYZ company is an oil
palm plantation company that develops information technology services to support the
company's business operations. In order for the purpose of developing XYZ company
information technology services in line with the company's vision, mission and
objectives, an appropriate framework is needed in preparing strategic planning. This
study aims to provide recommendations for designing IT blueprints using the
Enterprise Architecture TOGAF framework for the development of information
technology that can be applied in XYZ companies
The document discusses different ways to implement threading in Java programs. It provides code examples to demonstrate creating threads by extending the Thread class and implementing the Runnable interface. The code examples show printing output from both the main thread and child threads to illustrate threading concepts. Socket programming and RMI examples are also provided with code to implement client-server applications using threads.
Covering important topics of Classical Machine Learning in 16 hours, in preparation for the following 10 weeks of Deep Learning courses at Taiwan AI academy from 2018/02-2018/05. Topics include regression (linear, polynomial, gaussian and sigmoid basis functions), dimension reduction (PCA, LDA, ISOMAP), clustering (K-means, GMM, Mean-Shift, DBSCAN, Spectral Clustering), classification (Naive Bayes, Logistic Regression, SVM, kNN, Decision Tree, Classifier Ensembles, Bagging, Boosting, Adaboost) and Semi-Supervised learning techniques. Emphasis on sampling, probability, curse of dimensionality, decision theory and classifier generalizability.
This document provides information about SQL queries and joins. It begins by introducing SQL (Structured Query Language) which is used to communicate with databases and retrieve required information. It describes the basic CRUD (Create, Read, Update, Delete) functions of SQL. It then discusses different types of SQL queries - aggregate function queries, scalar function queries, and join queries. It provides the syntax and explanation of inner joins, outer joins (left, right, full) which are used to query data from multiple tables based on relationships between columns. The document is presented by Hammad, Bilal and Awais.
Learn how to use arrays in Java, how to enter array, how to traverse an array, how to print array and more array operations.
Watch the video lesson and access the hands-on exercises here: https://softuni.org/code-lessons/java-foundations-certification-arrays
A graph data structure consists of vertices and edges that relate the vertices. Common graph representations include adjacency matrices and adjacency lists. Depth-first search (DFS) is an algorithm for traversing graphs by going as deep as possible down each branch before backtracking. It uses a stack to remember to explore vertices later.
The document discusses different types of linked lists, including singly linked lists, doubly linked lists, and circular linked lists. Operations like insertion, deletion, concatenation, reversal, and representation of polynomials and sparse matrices are described. Singly linked lists use one pointer in each node, while doubly linked lists use two pointers - one for the next node and one for the previous. Circular linked lists connect the last node back to the first node to allow efficient erasing of the entire list. Linked representations allow flexible placement of nodes in memory and simpler insertion/deletion compared to sequential arrays.
- To translate an object by a vector v, each homogeneous vector p (written in homogeneous coordinates) would need to be multiplied by thistranslation matrix
simple pattern printing programme in c language for beginners.
here you can see code with its pattern programme and easily can understand the programme.
The document discusses various techniques for exploiting web applications, beginning with older techniques like exploiting default admin paths, uploading web shells, and SQL injection, and progressing to more modern attacks against content management systems and frameworks. It provides examples of each technique and emphasizes exploiting vulnerabilities like file inclusion and stored procedures to achieve remote code execution. The instructor profile indicates extensive security experience and certifications. The organization Secure D Center is introduced as focusing on cybersecurity services across Southeast Asia.
SQL is a language used to manage data in relational database management systems (RDBMS). This tutorial provides an overview of SQL and its components, introduces key SQL concepts like database objects, data types, and SQL statements, and includes many examples for working with SQL databases, tables, and queries. It covers common SQL statements like SELECT, INSERT, UPDATE, DELETE, and explains concepts such as aggregates, joins, subqueries and more.
This document discusses transaction processing in database management systems (DBMS). It describes the ACID properties that transactions must satisfy - atomicity, consistency, isolation, and durability. An example of a fund transfer transaction is provided to illustrate these properties. Concurrency control is discussed as a mechanism for allowing concurrent transactions while maintaining isolation. The concepts of schedules, conflicting instructions, conflict serializability, and view serializability are introduced for evaluating the correctness of concurrent transaction executions.
Basic Concept of discrete math. I discuss a few topic of basic discrete math. I think you get a clear concept. Topics are definition,story of discrete math, Importance of discrete math, and many other basic topic.
Volatile is often misunderstood and provides weak guarantees. It ensures operations are not optimized away and occur in memory, not just registers, but does not guarantee atomicity, ordering, or visibility to other threads. Memory barriers are needed to ensure ordering between memory operations visible to other threads and hardware. Demonstrations show that without barriers, threads may see unexpected results from reordered memory accesses. Compiler barriers also help prevent reordering at the compiler level without machine-level barriers.
Introduction to structured query language (sql)Sabana Maharjan
This document provides an introduction to structured query language (SQL). It discusses the two broad categories of SQL functions: data definition language and data manipulation language. The data definition language includes commands for creating database objects like tables and views, while the data manipulation language includes commands for inserting, updating, deleting, and retrieving data from tables. The document then covers topics like SQL data types, table structures, constraints, indexes, and basic data manipulation commands. It also discusses more advanced SQL concepts such as joins, aggregate functions, and views.
Java and Spring Data JPA: Easy SQL Data Access
Abstract
Presenter: Miya W. Longwe, MBA, MSE, Tech Lead, Staples, Inc, Framingham MA 01702
Accessing data repositories in various applications programming languages typically involves writing of tedious boilerplate lines of code. Some application development frameworks such as Spring have tried to make the experience more succinct by providing abstraction layers such as HibernateTemplate and JdbcTemplate, etc. Despite these APIs, the developers still spend a lot time writing repetitive code than concentrating on implementing business requirements. Developers at Spring, led by Oliver Gierke, introduced Spring Data JPA which “aims to significantly improve the implementation of data access layers by reducing the effort to the amount that's actually needed. As a developer you write your repository interfaces, including custom finder methods, and Spring will provide the implementation automatically”.
Spring Data JPA provides a powerful, out-of-the-box alternative to creating your own DAO framework. You declare custom repository operations on an interface, and the framework generates dynamic implementations (not code generation) automatically, based on conventions around method names. As part of the presentation, we'll also review a demo to look at Spring Java configuration (as opposed to XML configuration), and investigate the @Profile annotation – configuration details which may make life a bit easier in various ways when setting up unit testing of our repository classes, using out-of-the-box alternative to creating DAO framework, how to create custom repositories, pagination and support for custom queries among other features.
Presenter's Bio
Miya W. Longwe is a Senior Software Engineer and Tech Lead at Staples, Inc. where he is currently working on an initiative to re-platform the company’s ecommerce architecture to offer platform-driven, modular products that can be quickly customized, enhanced, and branded as needed.
Miya has been a software professional since 1997. His 16 years software development career includes working for large companies to small startups, building solutions for enterprises and consumers, working with a broad range of technologies.
Miya Longwe is a hands-on java developer. He believes that in order to be a relevant and effective software developer one needs to remain a deeply knowledgeable, up-to-date, and productive software developer. His research interests include model-driven engineering, domain specific languages, test driven development and project risk management.
Miya graduated from the University of Malawi (Lilongwe, Malawi) and has an MBA from the University of Wales Cardiff Business School (Wales, UK) and a Masters in Software Engineering from Brandeis University (MA, USA).
Occasionally, Miya can be spotted fishing the banks of the south shore (MA) with his two boys, William and Daniel.
The document is a lecture on the SQL language given at Trinity College. It introduces SQL as the standard language for relational databases and describes it as declarative, meaning the user specifies the desired results without specifying how to retrieve them. It then discusses some basic SQL statements like CREATE TABLE to define the structure of tables and import data types for attributes.
Sparse matrices are matrices that have relatively few nonzero elements, allowing for specialized storage techniques. They occur often in applications involving partial differential equations, text analysis, optimization, and network modeling. A sparse matrix example is presented with nonzero elements only in certain locations. Key sparse matrix types include triangular, banded, diagonal, and tridiagonal matrices.
DESIGNING IT BLUEPRINT WITH TOGAF FOR INFORMATION TECHNOLOGY DEVELOPMENTIAEME Publication
The use of information technology that is aligned with the company's goals will be
achieved if supported by a good governance planning system. Therefore, to develop
information technology can use the Enterprise Architecture approach as a guideline
or blueprint in the development of information technology. The XYZ company is an oil
palm plantation company that develops information technology services to support the
company's business operations. In order for the purpose of developing XYZ company
information technology services in line with the company's vision, mission and
objectives, an appropriate framework is needed in preparing strategic planning. This
study aims to provide recommendations for designing IT blueprints using the
Enterprise Architecture TOGAF framework for the development of information
technology that can be applied in XYZ companies
The document discusses different ways to implement threading in Java programs. It provides code examples to demonstrate creating threads by extending the Thread class and implementing the Runnable interface. The code examples show printing output from both the main thread and child threads to illustrate threading concepts. Socket programming and RMI examples are also provided with code to implement client-server applications using threads.
Covering important topics of Classical Machine Learning in 16 hours, in preparation for the following 10 weeks of Deep Learning courses at Taiwan AI academy from 2018/02-2018/05. Topics include regression (linear, polynomial, gaussian and sigmoid basis functions), dimension reduction (PCA, LDA, ISOMAP), clustering (K-means, GMM, Mean-Shift, DBSCAN, Spectral Clustering), classification (Naive Bayes, Logistic Regression, SVM, kNN, Decision Tree, Classifier Ensembles, Bagging, Boosting, Adaboost) and Semi-Supervised learning techniques. Emphasis on sampling, probability, curse of dimensionality, decision theory and classifier generalizability.
This document provides information about SQL queries and joins. It begins by introducing SQL (Structured Query Language) which is used to communicate with databases and retrieve required information. It describes the basic CRUD (Create, Read, Update, Delete) functions of SQL. It then discusses different types of SQL queries - aggregate function queries, scalar function queries, and join queries. It provides the syntax and explanation of inner joins, outer joins (left, right, full) which are used to query data from multiple tables based on relationships between columns. The document is presented by Hammad, Bilal and Awais.
Learn how to use arrays in Java, how to enter array, how to traverse an array, how to print array and more array operations.
Watch the video lesson and access the hands-on exercises here: https://softuni.org/code-lessons/java-foundations-certification-arrays
A graph data structure consists of vertices and edges that relate the vertices. Common graph representations include adjacency matrices and adjacency lists. Depth-first search (DFS) is an algorithm for traversing graphs by going as deep as possible down each branch before backtracking. It uses a stack to remember to explore vertices later.
The document discusses different types of linked lists, including singly linked lists, doubly linked lists, and circular linked lists. Operations like insertion, deletion, concatenation, reversal, and representation of polynomials and sparse matrices are described. Singly linked lists use one pointer in each node, while doubly linked lists use two pointers - one for the next node and one for the previous. Circular linked lists connect the last node back to the first node to allow efficient erasing of the entire list. Linked representations allow flexible placement of nodes in memory and simpler insertion/deletion compared to sequential arrays.
- To translate an object by a vector v, each homogeneous vector p (written in homogeneous coordinates) would need to be multiplied by thistranslation matrix
simple pattern printing programme in c language for beginners.
here you can see code with its pattern programme and easily can understand the programme.
The document discusses various techniques for exploiting web applications, beginning with older techniques like exploiting default admin paths, uploading web shells, and SQL injection, and progressing to more modern attacks against content management systems and frameworks. It provides examples of each technique and emphasizes exploiting vulnerabilities like file inclusion and stored procedures to achieve remote code execution. The instructor profile indicates extensive security experience and certifications. The organization Secure D Center is introduced as focusing on cybersecurity services across Southeast Asia.
SQL is a language used to manage data in relational database management systems (RDBMS). This tutorial provides an overview of SQL and its components, introduces key SQL concepts like database objects, data types, and SQL statements, and includes many examples for working with SQL databases, tables, and queries. It covers common SQL statements like SELECT, INSERT, UPDATE, DELETE, and explains concepts such as aggregates, joins, subqueries and more.
This document discusses transaction processing in database management systems (DBMS). It describes the ACID properties that transactions must satisfy - atomicity, consistency, isolation, and durability. An example of a fund transfer transaction is provided to illustrate these properties. Concurrency control is discussed as a mechanism for allowing concurrent transactions while maintaining isolation. The concepts of schedules, conflicting instructions, conflict serializability, and view serializability are introduced for evaluating the correctness of concurrent transaction executions.
Basic Concept of discrete math. I discuss a few topic of basic discrete math. I think you get a clear concept. Topics are definition,story of discrete math, Importance of discrete math, and many other basic topic.
Volatile is often misunderstood and provides weak guarantees. It ensures operations are not optimized away and occur in memory, not just registers, but does not guarantee atomicity, ordering, or visibility to other threads. Memory barriers are needed to ensure ordering between memory operations visible to other threads and hardware. Demonstrations show that without barriers, threads may see unexpected results from reordered memory accesses. Compiler barriers also help prevent reordering at the compiler level without machine-level barriers.
Introduction to structured query language (sql)Sabana Maharjan
This document provides an introduction to structured query language (SQL). It discusses the two broad categories of SQL functions: data definition language and data manipulation language. The data definition language includes commands for creating database objects like tables and views, while the data manipulation language includes commands for inserting, updating, deleting, and retrieving data from tables. The document then covers topics like SQL data types, table structures, constraints, indexes, and basic data manipulation commands. It also discusses more advanced SQL concepts such as joins, aggregate functions, and views.
2. Düzlemsel Çizge
• Herhangi bir ayrıtı başka bir ayrıt ile
kesişmeden bir düzleme çizilebilen çizgeye
düzlemsel çizge denir.
3. Bir çizgeyi düzlemsel hale çevirmek
• v1 ve v2, v4 ve v5 ikisine birden bağlı, bu dört ayrıt bir kapalı devre
oluşturlar.
• v3 çizmek istediğimizde ise bu ya R1 içinde ya da R2 içinde olması gerek.
• v6’yı herhangi bir kesişim yapmadan çizgenin içine yerleştirmek mümkün
değil.
4. Uygulama Alanı
• Bir çizgenin düzlemseliği elektronik devrelerin
tasarımı için önemli bir role sahiptir. Elektronik
bir devre bir çizge gibi gösterimlenebilir; tepeler
ve bunları birleştiren ayrıtlar olarak. Bir devre,
eğer onu temsil eden çizge düzlemsel ise tek bir
board üzerine basımı mümkün olabilir. Eğer
düzlemsel değilse bu çizge altçizgeler ayrılıp, çok
tabakalı devreler üretmek gerekir ki bu da daha
maliyetli bir çözümdür. Bunun dışında devrelerde
kesişim için yalıtılmış kablo kullanılabilir. Bu
durumda devrede az sayıda kesişim bulunması
önemli hale gelir.
5. Bölgeler ve Bölgelerin Derecesi
• Bir çizge düzlemi
bölgelere ayırır.
• Bir bölgenin
derecesi , o
bölgenin sınırını
oluşturan
ayrıtların sayısına
eşittir.
6. Bölgeler ve Bölgelerin Derecesi
• Bölgelerin derecelerinin toplamı çizgedeki
ayrıtların sayısının tam tamına iki katı olur,
çünkü her bir ayrıt bir bölgede iki defa
tezahür eder, ya aynı bölgede iki defa ya da
farklı iki bölge de birer defa olmak üzere
8. Euler Formülünün Kanıtı
• Bir düzlemsel çizgenin , bu başlangıç çizgesinden
başlayıp düzlemseliği bozmayacak şekilde birer
birer ayrıt eklenerek oluşan çizge için bu koşulun
doğru olduğunu bulabilirsek, Euler formülünü
kanıtlamış oluruz.
• Tümevarım Yöntemi
– Taban Adımı : bir ayrıt ve 2 tepe noktası G1
• r=e-v+2 => 1=1-2+2
– Tümevarım adımı:
• Yeni bir ayrıt ekleyerek bir çizge oluştur Gn+1
9. Euler Formülünün Kanıtı
• (a) için (r+1)=(e+1)-v+2 => r=e-v+2
• (b) için r=(e+1)-(v+1)+2 => r=e-v+2
• Her yeni eklenen {an+1, bn+1} ayrıtı için iki
ihtimal vardır:
10. Düzlemsel Çizge Teoremleri
• Her bir bölgenin en az 3 dereceli olduğunu söylemiştik. Bu
durumda
• Bölgelerin toplam derece sayısı >= 3*r
• Ayrıca bölgelerin toplam derece sayısı = 2*e
• Bu iki eşitliği kullanarak şuna varabiliriz
2*e>= 3*r => (2/3)e >= r
• Bu eşitliği Euler Formülüne yerleştirdiğimizde
r=e-v+2 => (2/3)e>=e-v+2
v-2 >= e/3 => 3v-6 >=e
11. Düzlemsel Çizge Teoremleri
• Birinci Teoremi kullanarak e<= 3v-6 ; eğer her bir tepe
noktasının derecesi en az 6 olsaydı;
• Tepe noktaların toplam derece sayısı = 2e (Handshaking
Teorem)
2e>=6v
• Fakat ilk Teoremden biliyorduk ki
e<= 3v-6 => 2e <= 6v-12
• Bu durumda 5 ten büyük olmayacak bir tepe noktası olması
gerek.
12. Düzlemsel Çizge Teoremleri
• Teorem 3:
e ayrıtı ve v tepe noktası olan bağlı basit bir
çizgenin v>= 3 olmak üzere 3 uzunluğunda bir
devresi yoksa, e<=2v-4 koşunu sağlar.
(2*e>= 3*r) => 2e >=4*r => e/2 >=r
r=e-v+2 => e/2 >= e-v +2
=> e <= 2v-4
14. Düzlemsel Olmayan Çizgeler
• K3,3 çizgesinde 3
uzunlukta herhangi bir
devre yoktur.
• e>= 2v-4 şartını
sağlaması gerekir
Fakat
9 <= 2*6 -4 =8 (Çelişki)
15. Kuratowski Teoremi
• Bir çizgenin K5 ve K3,3 çizgelerine homeomorf
bir altçizgesi varsa bu çizge düzlemsel değil.
– Bir çizgenin homeomorf çizgesi:
Derecesi iki olan her bir tepe noktasını silelim ve o
noktaya değen iki kenarı onarıp tek bir kenar
yapalım. Hatta, derecesi 0 ve 1 olan noktaları ve o
noktalara değen kenarları da atalım. Ve bunu
böylece sürdürelim. Geriye (belki de hiç noktasız)
her noktasının derecesi en az 3 olan bir çizge
kalacak. Oluşan çizge homeomorf çizgedir.