CS 117 Section 2 KNET

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CS 117 Section 2 KNET

• Computer accounts
• Emailed to KNET students
• Change password
• Homework 1
• Lab Tutors
• In lab for next 2 weeks
• Will help you with Linux, vi, email subscription

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Basic Programming

• What does a C program look like
• How do you use your computer account

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Linux

• Use your user name and password to log into
  emerald
• Use passwd command to change your password

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Processing a Program

• Editor used to enter the program
• Source program (file.cpp)
• UNIX vi text editor
• Compiler translates the source program
• Displays syntax errors (not descriptive)
• Linker/Loader to combine object file with other
  object files
• Executable program

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Processing a Program

• Major activities
• Editing - vi or other text editor
• vi hello.cpp
• Compiling/Linking - one step with g on emerald
• g hello.cpp
• g -o hello hello.cpp
• Running - type the executable name
• a.out
• hello

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shell.cpp

• / shell.cpp /
• include ltiostreamgt
• int main( void)
• cout ltlt "The first line of text"
• ltlt endl
• return 0

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input and output

• I/O in C uses streams
• cout ltlt "some text" ltlt endl
• cin gtgt someVar

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Program output

• cout is standard output stream
• monitor
• ltlt is an operator that inserts data into an
  output stream
• outStream ltlt data
• Text in double quotes is a constant string
• Hello, World!

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Program input

• cin is standard input stream
• keyboard
• gtgt is an operator that extracts data from an
  input stream
• inStream gtgt variable

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1.5 Software Development Method

• Problem Analysis - (Correct Problem)
• Identify data objects
• Goal to model properties
• Determine Input / Output data
• Constraints on the problem
• Design
• Decompose into smaller problems
• Top-down design (divide and conquer)
• Develop Algorithm (Desk check)

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Software Development Method

• Implementation
• Writing the algorithm
• Testing
• Verify the program meets requirements
• System and Unit test
• Documentation
• Key part in the development process

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Software Development Method

• Software engineering
• Area of computer science concerned with building
  large software systems
• Challenge
• Tremendous advances in hardware have not been
  accompanied by comparable advances in software