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Types of Iterative Statements
Python provides two types of iterative statements for and while.
The for Loop
The for loop executes a simple or compound statement for a fixed number of times, i.e
Prime (Ver. 2.2)-VIII 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:
Syntax
for <counter variable> in range(start, stop, step_size):
140 statements
The 'in' keyword is known as membership operator that is used to check whether the value
exists in a sequence or not. If the value is present in the sequence, the result is True,
else False. Python also provide another membership operator named 'not in'. The not in
operator is the opposite of the 'in' operator that checks if the value does not exist in the
sequence. If the value is not present in the sequence, the result is True else False.
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].

