Difference between revisions of "2015 Old Spec"
(→Figure 4) |
|||
| (4 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
=Question 4= | =Question 4= | ||
| − | + | ||
Create a folder/directory ''Question4'' for your new program. | Create a folder/directory ''Question4'' for your new program. | ||
| Line 11: | Line 11: | ||
==Figure 4== | ==Figure 4== | ||
| − | + | ||
| − | OUTPUT "The first few prime numbers are:" | + | :OUTPUT "The first few prime numbers are:" |
| − | FOR Count1 = 2 TO 50 DO | + | :FOR Count1 = 2 TO 50 DO |
| − | + | :: Count2 = 2 | |
| − | + | :: Prime = "Yes" | |
| − | + | :: WHILE Count2 * Count2 <= Count1 DO | |
| − | + | ::: IF (Count1 MOD Count2 = 0) THEN | |
| − | + | :::: Prime = "No" | |
| − | + | ::: ENDIF | |
| − | + | ::: Count2 = Count2 + 1 | |
| − | + | :: ENDWHILE | |
| − | + | :: IF Prime = "Yes" THEN | |
| − | + | ::: OUTPUT Count1 | |
| − | + | :: ENDIF | |
| − | ENDFOR | + | :ENDFOR |
| − | |||
==Table 3== | ==Table 3== | ||
| Line 49: | Line 48: | ||
|} | |} | ||
| − | + | ||
=What you need to do= | =What you need to do= | ||
| − | + | ||
Write a program for the algorithm in ''Figure 4''. Run the program and test that it works correctly. Save the program in your new ''Question4'' folder/directory. | Write a program for the algorithm in ''Figure 4''. Run the program and test that it works correctly. Save the program in your new ''Question4'' folder/directory. | ||
| Line 59: | Line 58: | ||
''+ 1 Mark for testing screenshot'' | ''+ 1 Mark for testing screenshot'' | ||
| − | + | ||
=Additional Question= | =Additional Question= | ||
| − | + | ||
Describe the changes that would need to be made to the algorithm shown in ''Figure 4'', so that instead of displaying the prime numbers between 2 and 50, inclusive, it displays all the prime numbers between 2 and a value input by the user, inclusive. | Describe the changes that would need to be made to the algorithm shown in ''Figure 4'', so that instead of displaying the prime numbers between 2 and 50, inclusive, it displays all the prime numbers between 2 and a value input by the user, inclusive. | ||
''3 marks'' | ''3 marks'' | ||
Latest revision as of 00:02, 29 November 2016
Question 4
Create a folder/directory Question4 for your new program.
The algorithm, represented using pseudo-code in Figure 4, and the variable table, Table 3, describe a program that calculates and displays all of the prime numbers between 2 and 50, inclusive.
The MOD operator calculates the remainder resulting from an integer division eg 10 MOD 3 = 1.
If you are unsure how to use the MOD operator in the programming language you are using, there are examples of it being used in the Skeleton Program.
Figure 4
- OUTPUT "The first few prime numbers are:"
- FOR Count1 = 2 TO 50 DO
- Count2 = 2
- Prime = "Yes"
- WHILE Count2 * Count2 <= Count1 DO
- IF (Count1 MOD Count2 = 0) THEN
- Prime = "No"
- ENDIF
- Count2 = Count2 + 1
- IF (Count1 MOD Count2 = 0) THEN
- ENDWHILE
- IF Prime = "Yes" THEN
- OUTPUT Count1
- ENDIF
- ENDFOR
Table 3
| Identifier | Data Type | Purpose |
|---|---|---|
| Count1 | Integer | Stores the number currently being checked for primeness |
| Count2 | Integer | Stores a number that is being checked to see if it is a factor of Count1 |
| Prime | String | Indicates if the value stored in Count1 is a prime number or not |
What you need to do
Write a program for the algorithm in Figure 4. Run the program and test that it works correctly. Save the program in your new Question4 folder/directory.
11 Marks
+ 1 Mark for testing screenshot
Additional Question
Describe the changes that would need to be made to the algorithm shown in Figure 4, so that instead of displaying the prime numbers between 2 and 50, inclusive, it displays all the prime numbers between 2 and a value input by the user, inclusive.
3 marks
