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As you know, 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.  However, 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 that 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
                  on a particular  test  condition,  a selection  or decision  making  statement  is  required.  Python
                  provides the following selection statements:

                  (i)  if statement                    (ii)  if-else statement   (iii)  if-elif-else statement

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



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