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08                        CONDITIONAL AND


                                                                       LOOPING STATEMENTS


                                                                                          IN BASIC-256









                    Your Aim

                    to learn about:
                          Conditional Statements                 Looping
                            For...Next Statement                   Sample Programs using For...Next Statement
                             While…END...WHILE Statement             Sample Programs using While…END...WHILE Statement
                               Infinite Loop


                  We make decisions in our daily life based on the conditions that we are in or the conditions that
                  we know we will face in a particular situation. For example, in the above situation, your decision
                  will be based on a condition; for example, if the lift is working, use it or else climb the stairs.
                  We face similar situations when we are programming. We have to make some decisions and
                  based on these decisions, the statements in the program are executed. In some conditions, our
                  program statements are based on the outcome. If the outcome is true, one set of commands is
                  executed and if the outcome is false, the other set of commands is executed.

                      CONDITIONAL STATEMENTS

                  Decision making in BASIC-256 is done by conditional statements or decision-making statements
                  that decide the direction of flow of program execution. Since they control the execution of the
                  program, we also call them Control statements. Control statements available in BASIC-256 are
                  given below:

                      IF-THEN Statement                                  IF-THEN-ELSE Statement
                  IF-THEN Statement

                  The  IF-THEN statement is  the simplest  conditional
                  statement. Here, certain  statement or block of                                         Execute
                                                                                      Is
                  statements within the if block is executed only if the                        Yes    statement(s)
                                                                                  condition
                  specified condition evaluates to true. If the condition
                  evaluates  to false, then  the  control  of  execution is          true
                  passed to the last statement, outside the if block.             No

                  The syntax of the IF-THEN statement is given below.
                  IF <condition> THEN                                           Statement after
                    Statements to be executed                                       END IF
                  END IF


                  68      Modular (Ver. 1.1)-VII
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