The document discusses various computing engineering topics such as using subprocesses to simplify program design, nested loops, arrays, and exam-like questions. It provides examples of how subprocesses can modularize complex programs and make them more reliable. Nested loops are described as loops within loops, where the inner loop iterates many times for each iteration of the outer loop. Basic array functions like assigning values, reading values, and searching are covered. Finally, there are examples of exam-like questions that could be asked involving these topics.

1. Computing in Engineering
Computers and Systems Engineering Dept

2. • Using Subprocesses to simplify program design
• Nested Loops
• Arrays
• Exam-like questions
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3. • Using Subprocesses to simplify program design
• Nested Loops
• Arrays
• Exam-like questions
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4. Using Subprocesses in Flowcharts
• Flowcharts of a complex process can
be broken down into smaller sub-
processes for clarity and re-usability.
• In this case a flowchart can point to a
different sub-process within its flow.
• The predefined process symbol to the
right is used to show such
subprocesses.
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5. The subprocess is useful because:
• it permits the modularization of complex programs.
• it provides a means of simplifying programs by making common
processes available to a wide number of programs.
• it makes for more reliable programs since once it is shown that a
process works then it can be made a subprocess and need not be tested
again.
• In flow charts subprocesses are also useful in dealing with the
flowcharting rule that a flow chart should have no more than 15 or so
symbols on a page.
Using Subprocesses in Flowcharts
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6. How to decide which sub-programs are needed?
• Break the program into subtasks
• Examine each subtask and break it down if
needed into further subtasks
• Continue until the subtask cannot be broken
down into small subtasks
• Example: Baking a cake
Using Subprocesses in Flowcharts
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7. What are things/tasks you have to do to make a
cake?
• Ingredient preparation
• Process the ingredients
• Assemble the cake
Using Subprocesses in Flowcharts
Example 1 : Baking a cake
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8. Using Subprocesses in Flowcharts
Example 1: Baking a cake
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9. Using Subprocesses in Flowcharts
Example 2: Read temperature in Fahrenheit and print its
value in both Fahrenheit and Celcius
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10. Using Subprocesses in Flowcharts
Example 3: Maximum of 3 Integers Revisited
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11. • Using Subprocesses to simplify program design
• Nested Loops
• Arrays
• Exam-like questions
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12. •Nested loops are loops placed inside one another
creating a loop of loops.
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13. Mock Example Revisited
Nested Loops
Pseudocode
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14. Nested Loops
Flowchart
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15. Problem: Design using flowchart
and pseudocode a program that
prints a figure similar to the one
on the right for a given number of rows
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16. Problem: Design using flowchart
and pseudocode a program that
prints a figure similar to the one
on the right for a given number of rows.
Analysis:
Inputs : None.
Variables: N, Row_No, where:
1. N = No of Rows = 9
2. Row_No changes from 1:N
Steps:
For each row
1. Calculate number of stars
2. Print ‘*’ ( N - Row_No +1 ) times on the same row
3. New Line
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17. Start
For Row_No =1 To N
No_of_stars=N-Row_No+1
For Col =1 To No_of_stars
Print ‘*’;
End For
New line
End For
Stop
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Hint:
Adding an “;” at the end of the Print statement
prevents skipping to the next line after printing

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19. • Typically used for
working with two dimensions (or more)
such as in the above example
•When a loop is nested inside another loop,
the inner loop runs many times
inside the outer loop.
•In each iteration of the outer loop,
the inner loop will be re-started.
•The inner loop must finish all of its iterations
•before the outer loop can continue to its next iteration.
•The inner loop must have a different name for its
loop counter variable so that it will not conflict with the outer loop.
For Row_No =1,N
No_of_stars=N - Row_No +1
For Col =1, No_of_stars
Print ‘*’
End For
New line
End For
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20. Design a program that types the binary numbers corresponding to the integers 0 – 7
Analysis:
Inputs: None
Define 3 variables A, B, C as the binary digits needed to represent the numbers from 0 -7
Initial values: A=0, B=0, C=0
Output: 0 000
1 001
2 010
.
.
7 111
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22. • Using Subprocesses to simplify program design
• Nested Loops
• Arrays
• Exam-like questions
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23. An array is a
collection of items of
same data type stored
at consecutive
memory locations.
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24. Basic array functions:
• Assigning values to
array elements
• Reading values
from array
elements
• Simple search
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25. Start
Read the number of elements n
Initialize i=0
Repeat
Read element no i
increment i
Until i = n
Initialize i=0
Repeat
write element no i
increment i
Until i = n
End
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26. Assumption:
The array “a” is already filled
with N numbers, and N >=0
Print
largest
End
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27. Given an array arr[] of N elements, the task is
to write a function to search a given
element x in arr[].
Example
Input: arr[] = {10, 20, 80, 30, 60, 50,110, 100,
130, 170}, x = 110;
Output: 6
Explanation: Element x is present at index 6
Input: arr[] = {10, 20, 80, 30, 60, 50,110, 100,
130, 170}, x = 175;
Output: -1
Explanation: Element x is not present in arr[].
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28. Input x, array
found = False
Length = array size
counter =0
WHILE found = False AND counter < length
IF array[counter] = x
THEN
Print counter
found = True
ELSE
counter = counter + 1
END IF
END WHILE
IF found = False
THEN
print 'Item not found’
END IF
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Input x, array
Length = array size
counter =0
WHILE counter < length
IF array[counter] = x
THEN
Print counter
counter = length
END IF
counter = counter + 1
END WHILE
IF counter = length
THEN
print 'Item not found’
END IF

29. • Using Subprocesses to simplify program design
• Nested Loops
• Arrays
• Exam-like questions
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33. Exam-like Question III
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34. Exam-Like Problem IV
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36. Thank You