Page 98 - Computer Science Class 11 With Functions
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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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