====== C++ Functions ======

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Examples (3/6/13):

  * [[cplusplus function prototypes | Function prototypes I]]
  * [[cplusplus inline functions | Inline functions I]]

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Answer and discuss the following questions:

  * [[cpluscplusfunctionreturn I | Function return I]]
  * [[cpluscplusfunctionreturn II | Function return II]]
  * [[cpluscplusvoidfunctions I | Void functions I]]
  * [[cpluscplusswapbyvalue | Functions by value]]
  * [[cpluscplusswapbyreference | Functions by reference]]

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Complete these programming projects:

1. Write and test the ''void'' function ''printfactorial( int n )'' that prints the factorial of an input integer. For example:

<code>
If printfactorial( 3 ), output is:

   3! = 3 * 2 * 1 = 6
   
If printfactorial( 4 ), output is:

   4! = 4 * 3 * 2 * 1 = 24

</code>

See [[printfactorial program developed in class]].

2. Write a C++ program ''printTable.cpp'' that utilizes looping and the tab escape sequence ''\t'' to print the following table of values:

<code>
   N    10*N    100*N   1000*N

   1    10      100     1000
   2    20      200     2000
   3    30      300     3000
   4    40      400     4000
   5    50      500     5000
</code>

3. Write a program ''evenFunction.cpp'' that inputs a series of integers and passes them one at a time to a function called ''even'', which uses the modulus (%) operator to determine whether the integers are even. The ''even'' function should take an integer input parameter and have an integer ''return'' type. The program should print whether each integer that you input is ''EVEN'' or ''ODD''.

4. In the program ''temperatureTable.cpp'' implement the following functions:

  * Function ''toCelsius'' returns the Celsius equivalent of a Fahrenheit temperature.
  * Function ''toFahrenheit'' returns the Fahrenheit equivalent of a Celsius temperature.

All inputs to and returns from the functions will be integer. Use these two functions in the ''temperatureTable.cpp'' program to print charts showing the Fahrenheit equivalents of all Celsius temperatures from 0 to 100 degrees, and the Celsius equivalents of all Fahrenheit temperatures from 32 to 212 degrees. Print the outputs in a neat tabular format that minimizes the number of lines of output while remaining readable.
   
Note:
     
   celsius = 5.0 / 9.0 * ( fahrenheit - 32 );
   fahrenheit = (9.0 / 5.0 * celsius) + 32 ;

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