post fix expression

Infix Postfix Prefix Notes A * B + C / D A B * C D / + + * A B / C D multiply A and B, divide C by D, add the results A * (B + C) / D A B C + * D / / * A + B C D add B and C, multiply by A, divide by D A * (B + C / D) A B C D / + * * A + B / C D divide C by D, add B, multiply by A

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data structure 2nd sessional course

Sessional course data structure:

v  Double link list( insertion , deletion , display)

v  Circular link list ( insertion , deletion , display)

v  Stack ( insertion , deletion , display)

v  Queue ( insertion , deletion , display)

v  Expression evaluation/polish notation( infix,prefix,postfix)e.g table from diagram

v  Tree(theory)

v  Tree traversial.

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Cardinality of Relationships

Cardinality is the number of entity instances to which another entity set can map under the relationship. This does not reflect a requirement that an entity has to participate in a relationship. Participation is another concept.
One-to-one: X-Y is 1:1 when each entity in X is associated with at most one entity in Y, and each entity in Y is associated with at most one entity in X.
One-to-many: X-Y is 1:M when each entity in X can be associated with many entities in Y, but each entity in Y is associated with at most one entity in X.
Many-to-many: X:Y is M:M if each entity in X can be associated with many entities in Y, and each entity in Y is associated with many entities in X (“many” =>one or more and sometimes zero)
 

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Keys in DBMS

Super key: An attribute or set of attributes that uniquely identifies an entity–there can be many of these
Composite key:A key requiring more than one attribute

Candidate key: a superkey such that no proper subset of its attributes is also a superkey (minimal superkey – has no unnecessary attributes)

Primary key: The candidate key chosen to be used for identifying entities and accessing records.  Unless otherwise noted “key” means “primary key”

Alternate key: A candidate key not used for primary key
Secondary key: Attribute or set of attributes commonly used for accessing records, but not necessarily unique
Foreign key: An attribute that is the primary key of another table and is used to establish a relationship with that table where it appears as an attribute also.

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Entities and Attributes

Entity Type:It is a set of similar objects or a category of entities that are well defined

• A rectangle represents an entity set
• Ex: students, courses
• We often just say “entity” and mean “entity type”

Attribute:It describes one aspect of an entity type; usually [and best when] single valued and indivisible (atomic)

• Represented by oval on E-R diagram
• Ex: name, maximum enrollment

Types of Attribute:

Simple and Composite Attribute

Simple attribute that consist of a single atomic value.A simple attribute cannot be subdivided. For example the attributes age, sex etc are simple attributes.

A composite attribute is an attribute that can be further subdivided. For example the attribute ADDRESS can be subdivided into street, city, state, and zip code. 

Simple Attribute: Attribute that consist of a single atomic value.

Example: Salary, age etc

Composite Attribute  : Attribute value not atomic.
Example :   Address  :  ‘House_no:City:State
Name      :  ‘First Name: Middle Name: Last Name’ 

Single Valued and Multi Valued attribute

A single valued attribute can have only a single value. For example a person can have only one ‘date of birth’, ‘age’ etc. That is a single valued attributes can have only single value. But it can be simple or composite attribute.That is ‘date of birth’ is a composite attribute , ‘age’ is a simple attribute. But both are single valued attributes.

Multivalued attributes can have multiple values. For instance a person may have multiple phone numbers,multiple degrees etc.Multivalued attributes are shown by a double line connecting to the entity in the ER diagram.

Single Valued Attribute: Attribute that hold a single value
Example1: Age
Exampe2: City
Example3:Customer id

Multi Valued Attribute: Attribute that hold multiple values.
Example1: A customer can have multiple phone numbers, email id’s etc
Example2: A person may have several college degrees

Stored and Derived Attributes

The value for the derived attribute is derived from the stored attribute. For example ‘Date of birth’ of a person is a stored attribute. The value for the attribute ‘AGE’ can be derived by subtracting the ‘Date of Birth’(DOB) from the current date. Stored attribute supplies a value to the related attribute.

Stored Attribute: An attribute that supplies a value to the related attribute.
Example: Date of Birth

Derived Attribute: An attribute that’s value is derived from a stored attribute.
Example : age, and it’s value is derived from the stored attribute Date of Birth.

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Concepts of Entity Relationship Diagram( ER diagram)

Entity Relationship Model:

An Entity – Relationship model (ER model) is an abstract way to describe a database. It is a visual representation of different data using conventions that describe how these data are related to each other.
There are three basic elements in ER models:

• Entities are the “things” about which we seek information.
• Attributes are the data we collect about the entities.
• Relationships provide the structure needed to draw information from multiple entities.

Symbols used in E-R Diagram:

• Entity – rectangle
• Attribute -oval
• Relationship – diamond
• Link - line

                                                                                             

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C++ Double Ended Queues

Constructors	create new deques
Operators	compare and assign deques
assign()	set the values of the deque
at()	returns a specific element
back()	returns the last element
begin()	returns an iterator to the first element
clear()	remove all elements
empty()	true if the deque is empty
end()	returns an iterator to the end of the queue
erase()	removes an element
front()	returns the first element
get_allocator()	returns the deque's allocator
insert()	insert elements into the deque
max_size()	returns the maximum elements that the deque can hold
pop_back()	removes the last element
pop_front()	removes the first element
push_back()	add an element to the end of the deque
push_front()	add an element to the front of the deque
rbegin()	returns a reverse iterator to the end of the deque
rend()	returns a reverse iterator to the beginning of the deque
resize()	change the size of the deque
size()	return the number of elements in the deque
swap()	swap one deque with another

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HEC LPTOP VALIDATION LINK FOR BS STUDENTS

 

laptop validation for bs by hec

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People Capability Maturity Model

The People Capability Maturity Model® (People CMM®) is a proven set of human capital man-

agement practices that provide a roadmap for cont

inuously improving the capability of an organization’s workforce. The People CMM refers to these practices asworkforce practices

. Since an organization cannot implement all of the best workforce practices in an afternoon, the People CMM introduces them in stages. Each progressive level of the People CMM produces a unique transformation in the organization’s culture by equipping it with more powerful practices for at-

tracting, developing, organizing, motivating, and retaining its workforce. Thus, the People CMM establishes an integrated system of workforce practices that matures through increasing alignment

with the organization’s business objectives, performance, and changing needs.

The People CMM was first published in 1995 [Curtis 95] and updated in 2001 [Curtis 02]. This

Second Edition updates informative material within the model, and provides new information re-

garding the global use of the People CMM. Since its first release in 1995, the People CMM has

successfully guided workforce improvement programs in many industries and geographies glob-

ally. The People CMM book has been in print in the US and elsewhere since its release in 2001.

Although the People CMM has been designed primarily for application in knowledge-intense or-

ganizations, with appropriate tailoring it can be applied in almost any organizational setting. Ad-

ditional information about application of the People CMM will be found in Chapters 7 and 8.

The People CMM’s primary objective is to improve the capability of the workforce. Workforce

capability can be defined as the level of knowledge, skills, and process abilities available for per-

forming an organization’s business activities. Workforce capability indicates an organization’s

readiness for performing its critical business activities,

•likely results from performing these business activities, and

•potential for benefiting from investments in process improvement or advanced technology.

In order to measure and improve capability, the workforce in most organizations must be divided

into its constituent workforce competencies. Eachworkforce competency represents a unique in-

tegration of knowledge, skills, and process abilities acquired through specialized education or

work experience. Strategically, an organization wants to design its workforce to include the vari-

ous workforce competencies required to perform the business activities underlying its core com-

petencies [Prahalad 90]. Each of these workforce competencies can be characterized by its capa-

bility—the profile of knowledge, skills, and process abilities available to the organization in that

competency. The People CMM describes an evolutionary improvement path from ad hoc, inconsistently per-formed workforce practices, to a mature infrastructure of practices for continuously elevating

workforce capability. The philosophy implicit in the People CMM can be summarized in the ten principles

1.In mature organizations, workforce capability isdirectly related to business performance.

2 Workforce capability is a competitive issue and a source of strategic advantage.

3 Workforce capability must be defined in relation to the organization’s strategic business objectives.

4 Knowledge-intense work shifts the focus fromjob elements to workforce competencies.

5 Capability can be measured and improved at multiple levels of the organization, including individuals, workgroups, workforce competencies, and the organization.

6 An organization should invest in improving the capability of those workforce competencies that are criti-cal to its core competency as a business.

7 Operational management is responsible for the capability of the workforce.

8 The improvement of workforce capability can be pursued as a process composed from proven practices

and procedures.

9 The organization is responsible for providing improvement opportunities, and individuals are responsible for taking advantage of them.

10 Because technologies and organizational forms evolve rapidly, organizations must continually evolve their workforce practices and develop new workforce competencies.

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