Page 110 - Computer Science V2.0 Class 11

In general, execution of statements involving a condition may be represented in a flowchart as shown in Fig 4.6.

Start

False Statement(s), when
Condition
condition is false

True

Statement(s), when
condition is true

Stop

Fig 4.6: Flowchart representation for branching based on some conditions
Pseudocode involving a condition may appear in any of the following two forms:

if condition then if condition then
Sequence of statements Sequence of statements

else

Sequence of statements
Fig 4.7 (a) involves an else part Fig 4.7 (b) Does not involve an else part

Example: Write a pseudocode to check whether a number is odd or even.
● Input: An integer (say, N)
● Process: Check whether N is divisible by two. If so, declare it even, otherwise declare that the number is odd.
● Output: Display the message:
Even: if N is divisible by two

Odd: if N is not divisible by two
Most programming languages provide the modulo operator (often denoted by the symbol %) which yields the remainder
on division. Thus, 32%5 yields 2 because by dividing 32 by 5 we get the remainder of 2 (32 = 5x6+2). Similarly, the
operators == and <> are used to test for the equality and inequality, respectively, of two numbers. Thus, 7==5 and
7 <> 5 yield False and True, respectively. Having learned the operators %, and ==, it is straightforward to write
pseudocode to check whether a number is odd or even.

input N

if N % 2 == 0 then
Print "Even"
else
Print "Odd"
Note that the string to be output printed is placed within the quotes (maybe single quotes or double quotes). However,
the computer will only print the text Even or Odd without any enclosing quotes.

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