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    Sometimes, you need to repeat a task multiple times or you may need to repeat the task either a
                      certain number of times or until a condition is satisfied. In Python, the statements that are used
                      to repeat a set of instructions are called iterative or looping statements. Looping statements are
                      very useful and necessary for developing applications.

                      Python provides two types of looping statements—for and while. The for statement is used to
                      repeat an instruction or a set of instructions for a fixed number of times. Whereas, the while
                      statement is used to repeat a set of instructions until a condition evaluates to true. Let’s discuss
                      these constructs in brief.

                                THE FOR LOOP

                      The for loop executes a simple or compound statement for a fixed number of times, i.e looping
                      a set of instructions for a specified number of times. For loop first initialises the counter variable

                      once, then it checks the range if within range it executes the statement within for loop and then
                      increments or decrements the counter variable as specified by step_size. The syntax of the for
                      statement is given below:

                      for <counter variable> in range(start, stop, step_size):

                          Statements
                      The range( ) function is an in-built function in Python. This function generates a sequence of
                      numbers. A sequence is a succession of values bound together by a single name. The range( )
                      function is generally used in the for loop to iterate over the sequence of numbers.

                      The general syntax for using the range( ) function is given below:
                          range(start, stop, step_size): The start specifies the starting point for generating numbers.

                         By default, it starts from 0. The stop specifies the position up to which the numbers are to be
                         generated (last number is not included). The step_size specifies the increment or decrement.
                         By default, the value of the step_size = 1 and numbers are generated with an increment of
                         1. However, we can generate numbers by specifying the value of step_size according to our
                         requirement.

                         range(start, stop): It generates a set of whole numbers starting from ‘start’ to ‘stop–1’.
                         Example: range(3, 9) is equivalent to [3, 4, 5, 6, 7, 8].

                         range(stop): Generates a set of whole numbers starting from 0 to (stop–1).

                         Example: range(6) is equivalent to [0, 1, 2, 3, 4, 5].

                      The start and step_size values are optional in the application of range() function and they can
                      be omitted.

                       80   Computer Science (V5.0)-VIII

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