Chapter 2

1
Chapter 2 Getting Started
2
(No Transcript)
3
Basic Program Structure

• include ltiostreamgt
• using namespace std
• int main( )
• cout ltlt This is C!

Lesson 2.1
4
C Syntax

• Rules for writing statements
• Semicolon serve as statement terminator
• Case sensitivity
• Blank spaces
• Spacing
• Accepted modifications

Lesson 2.1
5
Comments

• Notes in program describing what code does
• Perform no action in program
• Single line comment structure
• Begin with two slashes (no space between) //
• Line by itself or following statement
• Multiline comment structure
• Uses delimiters / comments /

Lesson 2.2
6
Creating a Banner

• Set of comments at beginning of program
• name
• parameters used
• history
• author
• purpose
• date of program

Lesson 2.2
7
Creating New Lines in Output

• Programmer must specify new line
• Line feeding
• \n in string constant
• cout ltlt \nwe can jump\n\ntwo lines.

• endl manipulator
• cout ltlt endlltltwe can jump
• cout ltlt endlltlt endl ltlttwo lines.

we can jump two lines.
Lesson 2.3
8
Connecting Strings

• Can use backslash at end of line to indicate
  string constant to continue with next line

cout ltlt This will \ continue on same line.
is equivalent to
cout ltlt This will continue on same line.
Lesson 2.3
9
Character Escape Sequences

• Other escape sequences exist for formatting
• Full listing in Table 2.1
• Examples
• \t horizontal tab
• \v vertical tab
• \ displays percent character
• \ displays double quote

Lesson 2.3
10
Debugging

• Error in program called bug
• Process of looking for and correcting bugs
• Three types of errors
• Syntax
• Run-time
• Logic

Lesson 2.4
11
Syntax Errors

• Mistakes by violating grammar rules
• Diagnosed by C compiler
• Must fix before compiler will translate code

coot ltlt endl
cout
int main ( (
)
Lesson 2.4
12
Run-Time Errors

• Violation of rules during execution of program
• Computer displays message during execution and
  execution is terminated
• Error message may help locating error

Lesson 2.4
13
Logic Errors

• Computer does not recognize
• Difficult to find
• Execution is complete but output is incorrect
• Programmer checks for reasonable and correct
  output

Lesson 2.4
14
Debugging Example
ltinclude iostreamgt using namespace std int main
( ) ( cout ltlt Hello world! cout ltlt
Hello again, endl // Next line will
output a name! ccut ltlt Sally
Student / Next line will
output another name / cout ltlt John Senior
include ltiostreamgt
OK
using namespace std
int main ( )

cout ltlt Hello world!
cout ltlt Hello againltlt endl
// Next line will output a name!
cout ltlt Sally Student
/ Next line will output another name
/
cout ltlt John Senior

15
Summary
Learned about

• General program structure
• Rules of C syntax
• Creating comments and program banners
• Using escape sequences to format output
• Debugging programs
• Three types of errors syntax, run-time, logic

Chapter 2