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As you know that a computer program is a set of instructions given to the computer to perform
            a specific task. These individual instructions are known as statements. All the statements are
            executed sequentially one after the other as they appear in a program but in some situations,

            we have to change the order of execution of the program based on certain conditions. In such
            situations, we use control statements to control or change the flow of execution.



                       CONTROL STRUCTURE

            A  control  structure is a programming  construct  which affects the flow  of the execution  of a
            program. Various types of control structures provided by Python are shown below:



                                                     Control Structure




               Sequential Statements                Selection Statements                 Iterative Statements



                     SEQUENTIAL STATEMENTS


            The statements that are executed in sequential order, i.e., one after the other without any jumps,
            are called sequential statements. A sequential structure is also known as a straight line path.




                                                        Statement 1



                                                        Statement 2



                                                        Statement 3





                     SELECTION STATEMENTS

            Some problems cannot be solved by performing a set of ordered steps as seen in sequential
            execution. When programmers are required to execute a particular set of statements depending

            upon a particular test condition, a selection or decision making statement is required. Python
            provides the following selection statements:
            (i)  if statement                    (ii)  if-else             (iii)  if-elif-else statement

            THE if STATEMENT

            The if statement is a decision-making statement which is used to control the flow of execution of
            statements.



            104   Pro (Ver. 5.0)-VIII
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