Procedure Orientated Coding

1
Procedure Orientated Coding

• Sequence
• Selection
• Loops
• Functions

2
While Loops

• while(condition)
• statement
• // Make sure statement eventually meets the
  condition

3
For Loops

• for(i0ilt45i)
• statement

4
Conditions

• While, If
• lt, gt, lt, gt, , !,
• For
• lt, gt , lt, gt

5
Functions or subprograms

• main
• Built in functions (sqrt(25))
• Subprograms
• Same as a main function in many ways
• Takes arguments like sqrt root e.g. 25

6
Function call from main

• include ltblah.hgt
• //Declare function
• int FunctionName(int var1,int var2)
• void main( )
• int var1,var2,var3
• var3FunctionName(var1,var2)

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Function

• int FunctionName(int v1,int v2)
• int v3
• statements
• return v3

8
Function

• int FunctionName(int v1,int v2)
• int v3
• statements
• return v3

9
Object Orientated Coding

• Input and output files

10

• include ltfstream.hgt //Needed for Input Output
  file streams
• void main()
• // Declare file stream
• ifstream file1
• // Open file
• input_file.open("test.dat")
• // read in inputs
• input_file gtgt number
• // Close files
• input_file.close()

11

• include ltstdlib.hgt //Needed to exit program
• char filename21
• cout ltlt "Please enter the name of the input file
  you wish to open" ltlt endl
• cin gtgt filename
• input_file.open(filename,iosnocreate)
• if(input_file.fail())
• cout ltlt "\n Input file failed to open, please
  check that the"
• cout ltlt " file exists" ltlt endl
• exit(1)

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Object ifstream functions

• input_file.open() input_file.eof()
• input_file.close() output_file.put
• input_file.fail()
• input_file.ignore()
• input_file.get()
• input_file.getline()
• input_file.peek()

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File Options

• input_file.open(file,iosnocreate)
• input_file.open(file,iosin)
• output_file.open(file,iosout)
• input_file.open(file,iosapp)
• input_file.open(file,iosate)
• input_file.open(file,iosbinary)
• input_file.open(file,iostrunc)
• input_file.open(file,iosnoreplace)

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setiosflags(iosoptions)

• showpos Show
• scientific Scientific notation
• dec Decimal base 10
• oct Octal base 8
• hex Hexadecimal base 16
• fixed Show as decimal
• showpoint Show decimal point
• right Right Justify

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stdlib.h

• exit()

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Type Coercion

• Float to Integer Truncates
• Integer to Float Adds .0
• Integer to Character Gives ASCII
  number for that integer
• Float to character Truncates and
  converts to ASCII

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ASCII

• Integers 0-9 ASCII 48-57
• Lower case alphabet a-z ASCII 97-122
• Upper case alphabet A-Z ASCII 65-90
• Means can order alphabet in an if
• if (alt b) //is true
• if (jltc) // is false

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Object string functions

• find () find the argument in the string,
  returns position in string (starting at 0)
• substr(a,b) returns segment of string from a to
  b
• length(),size() returns length of string

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Arrays

• int number1,number2,number3
• sumnumber1number2number3
• Or
• int number3
• sumnumber0number1number2

20
Conversion String to Number

• Need stdlib.h and math.h
• atof() string to float
• atoi() string to integer