Assignment #4 - Functions

Objective

Task

• seconds.cpp
• dice.cpp

Exercise 1

1. Write a function called Seconds that takes in three integer parameters (representing hours, minutes, and seconds) and returns the number of seconds since the last time the clock "struck 12" (i.e. was at 12:00:00 -- AM or PM doesn't matter since you're not tracking this).
    
2. To test this function, write a main() routine (in the same file) that prompts the user to enter hours, minutes, and seconds for two different clock times; then uses the Seconds function to calculate the shortest amount of time in seconds between the two times (both of which are within one 12-hour cycle of the clock); the print out the number of seconds since "striking 12" for both clocks, as well as the number of seconds between the two clock times

Sample Run 1:

  Input first clock time...
  Hours: 6
  Minutes: 45
  Seconds: 30

  Input second clock time...
  Hours: 4
  Minutes: 50
  Seconds: 12

  It's been 24330 seconds since the first clock struck 12:00
  It's been 17412 seconds since the second clock struck 12:00
  The two times are 6918 seconds apart.

Sample Run 2:

  Input first clock time...
  Hours: 12
  Minutes: 43
  Seconds: 16

  Input second clock time...
  Hours: 7
  Minutes: 11
  Seconds: 59

  It's been 2596 seconds since the first clock struck 12:00
  It's been 25919 seconds since the second clock struck 12:00
  The two times are 23323 seconds apart.

Exercise 2

1. Write a function called RollDice that returns the result from rolling two standard six-sided dice)
   • The function will take no parameters, but it will return the resulting total of the dice roll as an integer
   • Remember that the rolling of a die involves randomness, so you'll need to use the random number generation functions discussed in class (see online notes).
   • Note that rolling two 6-sided dice is NOT equivalent to picking a random number from 2 through 12. This is because when you roll 2 dice, there is a much larger change of hitting some totals than others. You need to roll two dice and add them together
   
   
2. To test this function, write a main() routine that does the following:
   • Ask the user to enter how many times they want to roll the dice, and let them enter a value (for this writeup, I'll call it N)
   • Call the RollDice function this many times (i.e. N times), and count how many times a total of 2 (known as "Snake Eyes") appears, as well as how many times a total of 7 appears.
   • For each of these totals (2 and 7), print out how many times that total appeared, as well as what percentage this is of the total number of rolls. Percentages should be printed to 2 decimal places.
   
   
3. Note: When you seed the random number generator, go ahead and use the time function, as illustrated in the class notes

Sample Run 1

How many times would you like to roll the two dice? 10000

Snake eyes (double 1s) appeared
   268 times
   2.68 % of the time

A roll of 7 appeared
   1675 times
   16.75 % of the time

Sample Run 2

How many times would you like to roll the two dice? 500000

Snake eyes (double 1s) appeared
   13706 times
   2.74 % of the time

A roll of 7 appeared
   83300 times
   16.66 % of the time

Sample Run 3

How many times would you like to roll the two dice? 500000

Snake eyes (double 1s) appeared
   13921 times
   2.78 % of the time

A roll of 7 appeared
   83789 times
   16.76 % of the time

Requirements for all programs

• No global variables, other than constants
• The required tasks must be performed with the functions specified (not just with a single main() routine)
  • Note that each exercise requires the writing of a function, and a main routine to test that function.
  • Each function should do exactly the task specified in item 1 of each exercise
  • Item 2 of each exercise specifies what to do in main() -- this will always involve CALLING the function, sometimes more than once
  • Note that there is NO keyboard-input/screen-output specified in the functions themselves (i.e. "return" does not mean "print")
• All input and output must be done with streams
• You may use the iostream and iomanip libraries (the ones that have been discussed in class)
• For exercise 2, you'll need the cstdlib and ctime libraries
• When you write source code, it should be readable and well-documented.
• Your program should only use standard ANSI header files (make sure to follow the directions exactly on the handout for creating Visual C++ projects, so that Windows-specific headers like stdafx.h and conio.h are not placed into your file)

Submitting:

 seconds.cpp
 dice.cpp