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CONDITIONAL STATEMENTS

               08                                                                          IN PYTHON















                                 Your Aim

                                 to learn about:
                                        Decision Making Statements       The if Statement
                                         The if…else Statement             Nested if Statement
                                          The if…elif…else Ladder


            There are situations in life when we need to decide based on a situation. For example, if it rains,
            I will stay at home or else I shall visit the market. Similar situations arise in programming as
            well, where we need to make some decisions and based on these decisions, execute a set of
            commands. We need to determine which action is to be taken and which statement is to be
            executed, if the outcome is true or false. In this chapter, we will learn about decision making
            statements of Python.

                DECISION MAKING STATEMENTS

            Decision making in Python is done by called conditional statements which decide the flow of
            program execution. The following conditional statements are available in Python:

                if statement                        if...else statement
                Nested if statement                 if…elif…else ladder

                THE IF STATEMENT

            The if statement is the simplest conditional statement. Here,
                                                                                                        False
                                                                                    Test Expression
            a statement or a collection of statements within the if block
            is executed only if a certain condition or expression evaluates
            to True. If the condition evaluates to False, then the control                 True
            of execution is passed to the next statement after the if block.
            The syntax of the if statement is given below:                             Body of if

            Syntax:

            if (Test Expression):
                                                                                 Statement just below if
                Indented statement block
            # if block ends here


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