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FEU – EAST ASIA COLLEGEInformation
Technology
Department
Module 2
Flowcharting and
Pseudo-coding
Engr. J. Cansino
Program Elements
&
Structure
Program Elements and Structure
1.) Constants – Literal Value that does not change during
program execution. It can be of the numeric or string type.
Numeric Constant - may be an integer (whole number) or a
real number (with a decimal place). It may be preceded by a
positive or negative sign.
Examples:
10 -28 +3.4 -0.413 0 201
Note: No other characters must or can appear together with the
constants. The following are examples of incorrect numeric
constants:
10,000 $14.3 10mi/hr 1/2
String Constant – A character or group of characters enclosed
in double quotation marks ( “ ). The numbers 0-9, letters a-z or
A-Z and all special characters like a space, % $ - _ & etc. may
be included.
Examples:
“J” “Jojo” “.” “1225” “J & J”
Note: The entire string constant must always be enclosed in
double quotation marks, one before the first character and one
after the last character (no more no less). The following are
examples of incorrect string constants:
“Earl Jerald Cansino” “SMART” “Avenger Assemble”
2.) Variables – Is a portion of the computer’s main memory
used to store a numeric or string constant. The value stored in
the variable must be given a unique variable name but it can
only hold one value at a given time.
Variable names must conform to the following
requirements:
a.) Must contain only letters, numbers and/or an underscore.
b.) Must begin with a letter.
c.) Must end either with a letter or a number.
d.) Must be unique that is, not a name of another variable.
e.) Must not be a keyword like ACCEPT, WHILE and the
like.
A variable may be one of the following types:
Numeric, String, Array
Note: Variable names are not case sensitive in
flowcharting and pseudo-coding, that is, upper and
lower case letters are not differentiated. For
example the variable TOTAL is the same as total.
The following are example of incorrect variable
name:
Year code 10ctr #5 Total=
3.) Expressions – is a group of program
elements consisting of operands and operators.
Operands can be a constant, variable, and or
an array element. Operators can be arithmetic,
logical, relational and/or string. Expressions
always yield a value of a certain type depending on
the type of expressions used.
Arithmetic Expressions
Hierarchy or Priority of Operators
1.) Expressions in parenthesis
2.) * / %
3.) + -
Examples:
1.) 10 + 4 * 8
2.) 50 % 6 – 5
3.) 20 / 4 * 9
32
42
2
-3
5
45
String Expressions
Examples:
1.) “3” + “4” = “34”
2.) “Ja ” + “red” = ”Jared”
Examples of incorrect usage of the +
operator:
“3” + 4 100 + “Peso”
Relational Expressions
Greater than >
Less than <
Greater than or equal to >=
Less than or equal to <=
Not equal !=
Is equal to ==
Examples:
Ctr1 > 10 3 <= 5 Temp1 != Temp2
Examples of incorrect Relational Expressions:
30 <= X <= 40 43 > < 50
Logical Expressions
Hierarchy or Priority of Operators
1.) Expressions in parenthesis
2.) Not (!)
3.) And (&&)
4.) Or (||)
TRUTH TABLE FOR NOT(!)
X !X
FALSE TRUE
TRUE FALSE
TRUTH TABLE FOR AND(&&)
X Y X && Y
FALSE FALSE FALSE
FALSE TRUE FALSE
TRUE FALSE FALSE
TRUE TRUE TRUE
TRUTH TABLE FOR OR(||)
X Y X || Y
FALSE FALSE FALSE
FALSE TRUE TRUE
TRUE FALSE TRUE
TRUE TRUE TRUE
Examples:
15 >= 10 && 15 <= 20
T && T
T
4.) Statements – are keywords, which perform
which perform a predefined procedure. The following
statements are available:
1.) DISPLAY Statement
2.) ACCEPT Statement
3.) IF Statement
4.) WHILE Statement
5.) FOR Statement
Assignment #1.1 Evaluate the
following expression.
1.) 11 % 2 + 3 * 7 –2
2.) 100 % 5 % 3 % 2
3.) – (45 / 9) * 6 + 4
4.) (5 + 7) % (10 * 2 – 5) / (15 – (8 – 6 % 4))
5.) (8 + 21 % (18 – 5 * 3)) % (17 – (6 + 13 % 5))
6.) (12 == 12 % 2 * 2) && !(( 5 > 3) && (8<3))
7.) (6 > 3) && (8 != 8) || !(10 <= 10)
8.) 15 / 3 == 15 % 39.) 5 != 11 / 2
10.) (100 * 24)/12 + 45
Assignment #1.2
Check if Valid (V) or Invalid (I)
1. Numeric Constant: “0.12345”
2. String Constant: HELLO_TRISHA
3. Arithmetic Expression: (45.9)%(5*2%3)
4. Variable Name: _J_A_R_E_D
5. Relational Expression: (5<=2*2) =10+1
6. Logical Expression: (!(!(!(F&&T))))
7. Variable Name: J5R3D
8. String Constant: “*&****hello##”
9. Numeric Constant: 1,000,000.98
10. Logical Expression: (!T&&!F)||(!F)
Evaluate the Following expressions:
1. 12 % 6 + (2 + 12 * 3) – ( 12 % 13)
2. (10 / 3 + (16 + 3) )– ((5 * 2 % 10) + 2)
3. (T || F) && (!(!F && (6 > 8) || (5< 10) || F) || !T)
4. (T || !F) || (!(!(!F || (3 < 15) || F) || !F) && T)
5. !(!T && !F) || (!T || (12 <= 12) || (T && F)|| F)
FLOWCHARTS
- A graphic form of an algorithm.
- A diagram of a sequence of steps that a program
must perform to produce the desired output.
- Traditional tool of programmers which allow flexibility
in terms of detail to be included.
TYPES OF FLOWCHARTS
1.) System Flowchart – present the total picture
without worrying about taking care of every detail.
2.) Program Flowcharts – depicts a main segment of
a complete computer program.
FLOWCHARTING GUIDELINES
1.) Always use the ANSI standard symbols.
2.) Construct your flowcharts to read from top to
bottom and left to right.
3.) Do not crisscross flowlines (used labeled
connectors and use arrowheads to indicate direction
of the flow.
4.) Make the messages and labels in the flowchart
symbol direct and descriptive.
5.) Strive for neatness, clarity and simplicity.
BASIC FLOWCHARTING SYMBOLS
Terminal Symbol
Decision Symbol
Preparation Symbol
Processing Symbol
Input/Output Symbol
Offpage Connector
Predefined Process Symbol
Onpage Connector
Flow Direction Lines
Sequential Program
Structure
For Flowchart, symbols used are the following:
Terminal symbol
I/O symbol
Preparation symbol
Direction lines
For Pseudocode, keywords used are the following:
1.) Accept
Syntax: Accept <variable>
Accept <variable1>, …, <variableN>
2.) Display
Syntax: Display “<string>”
Display <variable>
Display <variable1>, …, <variableN>
Sequential structure
#1] Input a temperature in Celsius and
output the corresponding temperature in
Fahrenheit. The formula is a follows:
Fahrenheit = 9 (Celsius) + 32
5
FlowchartStart
F = 0
Input C
F = (9.0/5.0) * C + 32
Output F
End
Pseudocode
Variables Used:
F, C are numeric
Begin
F = 0
Display ” Input temperature in Celsius: ”
Accept C
F = (9.0 / 5.0) * C + 32
Display “Equivalent temperature in
Fahrenheit:”, F
End
Sequential structure
#2] Pepperoni++ Pizza House charges 10%
service charge and 5% sales tax on the gross
bill of the customer. Create a flowchart and a
pseudocode that would input the gross bill of the
customer and the amount given by the customer
to the waiter. It must output the customer’s total
bill and change (if there’s any).
Flowchart
Start
TBill = 0
change = 0
Input GBill, Amt
TBill = Gbill + Gbill *0.1 + Gbill * 0.05
change = Amt - TBill
Output TBill, change
End
Pseudocode
Variables Used:
GBill, Amt, change, TBill are numeric
Begin
TBill = 0
change = 0
Display ” Input Gross Bill and Amount Given: ”
Accept GBill, Amt
TBill = GBill + GBill * 0.1 + GBill * 0.05
change = Amt - TBill
Display “Total Bill = ”, Tbill
Display “Change = ”, change
End
Assignment #1.2: Sequential structure
#5] Using Visual Logic, Draw and execute a FCD for
Workers at a particular company were given a 15.5%
salary increase. Moreover, the increase was
retroactive for 2 months, that is, effective two months
ago. Create a flowchart and a pseudocode that takes
the employee’s old salary as input and then output
the amount of retroactive pay (balance) due the
employee and his new salary as well.
SELECTION /
CONDITIONAL PROGRAM
STRUCTURE
For Flowchart, symbols used are the following:
Terminal symbol
I/O symbol
Preparation symbol
Flow Direction lines
Decision symbol
For Pseudocode, keywords used are the
following:
1.) Accept
Syntax: Accept <variable>
Accept <variable1>, …, <variableN>
2.) Display
Syntax: Display “<string>”
Display <variable>
Display <variable1>, …, <variableN>
3.) if-then-else
Syntax #1: if <condition> then
begin
statements
.
.
.
end
else
begin
statements
.
.
.
end
Syntax #2: if <condition1> then
begin
statements
end
else if <condition2> then
begin
statements
end
else if <conditionN> then
begin
statements
end
else
begin
statements
end
Selection/Conditional Structure
#1] Using Visual Logic, create a
flowchart and a pseudo-code that
will prompt the user to input two
number and output the highest
number entered.
FlowchartStart
Input N1, N2
End
If
N1 > N2
N
Output N2
Output N1
Y
A
A
Pseudocode
Variables Used:
N1, N2 are numeric
Begin
Display ” Input two numbers: ”
Accept N1, N2
if (N1 > N2) then
Display N1
else
Display N2
End
Assignment # 1 .3 Selection Structure#1] The fine for an over-speeding violation depends on the
speed of the erring driver, as follows:
60 to 75 mph = Php 2000.00
76 mph and above = Php 4000.00
Create a flowchart and a pseudocode to input the car’s
speed and then output the fine, if any.
#2] In the game of JACK N POY each of the two player
choose either a scissors (code X), paper (code P), or stone
(code S). If one chooses scissors and the other chooses
stone then stone wins. If one chooses paper and the other
stone then paper wins. If one chooses paper and the other
scissors then scissors wins. If they both choose the same
then the result is a tie. Create a flowchart or a pseudocode
that will input two character codes corresponding to the
object selected and then output either the message “PLAYER
1 WINS” or “PLAYER 2 WINS”
#3] Bongga Ka Day Inc. gives additional performance
bonuses to its employees every year. The amount is
dependent on the number of years of service of the
employee as follows:
Years of Service Amount of Bonus
5 years and below 50% of monthly salary
6 years to 10 years 100% of monthly salary
11 years to 25 years Php 30,000.00 or twice
the monthly salary,
whichever is higher.
ITERATIVE/ LOOPING
PROGRAM
STRUCTURE
For Flowchart, symbols used are the following:
Terminal symbol
I/O symbol
Preparation symbol
Flow Direction lines
Decision symbol
For Pseudo code, keywords used are the following:
1.) Accept
2.) Display
3.) if-then, if-then-else
4.) while-do
Syntax:
while <condition> do
begin
statements;
end
.
.
.
Iterative Program Structure
#1] Create a flowchart/pseudo code that will
generate the following number series:
10, 5, 9, 10, 8, 15, 7, 20, 6, and 25
FlowchartStart
End
If
X >= 6
N
Y
X = X – 1
Y = Y + 5
Output X, Y
X = 10Y = 5
Pseudo code
Variables Used:
X, Y are numeric
Begin
X = 10
Y = 5
while (X >= 6) do
begin
Display X, Y
X = X – 1
Y = Y + 5
end
End
Iterative Program Structure
#2] Create a flowchart/pseudo code that will
generate the following number series:
1, 1, 2, 3, 5, 8, 13, 21, 34, and 55
FlowchartStart
End
If
Sum <= 55
N
Y
Sum = X + Y
X = Y
Y = Sum
Output Sum
X = 0Y = 1
Sum = 1
Pseudo codeVariables Used:
X, Y, Sum are numeric
Begin
X = 0
Y = 1
Sum = 1
while (Sum <= 55) do
begin
Display Sum
Sum = X + Y
X = Y
Y = Sum
end
End
Assignment #1.4 Iterative Program Structure
Using Visual Logic:
#1] Create a flowchart/pseudo code that will
input five numbers and output how many of
the numbers entered are odd or even.
#2] Create a flowchart/pseudo code that will
input five numbers and output how many
of the numbers entered are positive or
negative.
Assignment #1.3 Iterative Program Structure
#3] Create a flowchart/pseudo code that will input 10
alphabetic characters and output how many of the
characters entered were vowels and consonants.
Disregard characters that are not alphabetic.
#4] Create a flowchart/pseudo code that will input 5
numbers and output the highest number entered.
#5] Create a flowchart/pseudo code that will input 6
score for quizzes (0-100). Eliminate the lowest quiz
and compute and output the average of the five
remaining quizzes.
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