Session 6
Complex
Conditionals
CSC 104international, open membership, notfor-profit technology
standards
Programming
Logic
Pearson Custom
consortium.
Computer Science
and Problem Solving
CSC 104
Nassau Community College
Prof. Vincent Costa
Nassau Community College
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Programming Using Visual Basic 2012, All
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From Last Class
• Simple if statements with one condition and one
possible action:
if (grade = 100) then
perfect score
end if
• Simple if/else
statements
one condition
and two
international,
openwith
membership,
notpossible actions:
for-profit technology standards
if (grade >= consortium.
70) then
pass
else
fail
end if
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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2
Introduction to Logical Operators
• Sometimes you want to evaluate two or
more conditions in order to make a
decision.
international,
open membership,
• Conditions
are combined
using notlogical
for-profit technology standards
operators.
consortium.
• Logical operators (OR, AND, NOT) –
explain complex conditions. Used in truth
tables
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Introduction to Logical Operators
X
NOT X
True
False
False
True
True
international, open membership, notY
X OR Y
X
Y
for-profit
technology standards
Trueconsortium.
True
True
True
True
False
True
True
False
False
False
True
True
False
True
False
False
False
False
False
False
False
X
Prof. Vincent Costa
Nassau Community College
X AND Y
True
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Introduction to Logical Operators
• Let’s say you want to determine whether or
not it is the proper day/time for CSC104.
How would you write that as a complex
condition?
international, open membership, notfor-profit technology standards
if (day = consortium.
“Tuesday”) AND (time = 1pm) then
CSC 104
end if
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Complex Conditions – If Statement
• Structure:
if (condition1) logicOperator (condition2) then
statement(s) to be executed if the complex
condition evaluates to TRUE
else
international, open membership, notfor-profit technology
standardsif the complex
statement(s)
to be executed
consortium.
condition
evaluates to FALSE
end if
• Logic Operators: AND, OR
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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6
Example 1
Complex if and if/else
Results for each of the
statement example
different values
if (average >= 70) AND
values for average:
(average < 80) then
60:
open membership,
grade isinternational,
C
70: grade notis C
for-profit technology standards
end if
75: grade is C
consortium.
80:
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Example 2
Complex if and if/else
Results for each of the
statement example
different values
if (average >= 70) OR
values for average:
(average < 80) then
60: grade is C
open membership,
grade isinternational,
C
70: grade notis C
for-profit technology standards
end if
75: grade is C
consortium.
80: grade is C
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Example 3
Complex if and if/else
Results for each of the
statement example
different values
if (age < 12) OR (age
values for age:
>=65) then
10: discounted ticket
international,
notdiscounted
ticket open membership,
12: regular
ticket
for-profit technology standards
else
25: regular ticket
consortium.
regular ticket
65: discounted ticket
end if
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Example 4
Complex if and if/else
Results for each of the
statement example
different values
if (age < 12) AND (age
values for age:
>=65) then
10: regular ticket
international,
notdiscounted
ticket open membership,
12: regular
ticket
for-profit technology standards
else
25: regular ticket
consortium.
regular ticket
65: regular ticket
end if
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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More Logical Operators
• You can use more than 1 logical operator in a
complex condition – for example:
if ((day = “Tuesday”) AND (time = 10am)) OR
((day =international,
“Wednesday”)
AND (time = 9:30am))
open membership, notthen
for-profit technology standards
CSC 104
consortium.
end if
• Order of precedence: use parenthesis, if no
parenthesis ANDs are executed first then
ORs.
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Nested if/else
• What if we have more than 2 possible actions
or multiple values to be checked?
• We can use additional conditions by placing one
if statement within another if statement –
this is called
nesting
if membership,
statements.
international,
open
notfor-profit technology standards
• For example:
Let’s say aconsortium.
sporting event charges different prices
based upon where a seat is located – seats in the
lower balcony cost $100, seats in the middle section
cost $60 and seats in the upper deck cost $25.
How would you determine the seat price?
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Nested if/else
if (seatLocation = “lower balcony”) then
price is $100
else
if (seatLocation = “middle section”) then
price is $60
international, open membership, notelse
for-profit technology standards
price isconsortium.
$25
end if
Notice: we don’t need to check if the seat is located in the
upper deck because that is the only other option, known as
the default
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Review & Exercises
• Review and do the exercises in Boolean Ops
and Nested Conditional Exercises
international, open membership, notfor-profit technology standards
consortium.
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
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Homework #4
• Use Blackboard or hand in on Wednesday
or mail (vincent.costa@ncc.edu)
• Please try to do it with Blackboard! 
international, open membership, notfor-profit technology standards
consortium.
Prof. Vincent Costa
Nassau Community College
Acknowledgements: An Introduction to
Programming Using Visual Basic 2012, All
Rights Reserved
15