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    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

                                                                                                   Start
                      THE if STATEMENT
                      The if statement is a decision-making statement that is used
                                                                                                                   False
                      to  control the  flow of execution  of statements.  It contains  a        if condition
                      conditional  expression,  which is  used  to  compare data.  A

                      decision is made based on the result of the comparison. If the                  True
                      result of the expression  is  true, the  statements  within  the  if   Statements in if block
                      block are executed and if the result of the expression is false,           execute
                      the statements within the if block are not executed.
                                                                                                   Stop

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