Page 132 - Computer Genius Class 08
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for Loop

                   he for statement executes a simple or compound statement for a fixed number of times.  he for
                  loop in Python is used to iterate over a sequence (list, tuple, string) or other iterable objects.

                  Syntax:
                    for x in range(n):
                      Statement1
                      Statement2
                      . . . . . . . . . .

                  l   Here 'in' is the 'in operator' that checks whether the specified value is in the sequence or not. This
                     statement always outcomes to Boolean values i.e,. True or False.
                  l   The body of ‘For’ loop is separated from the rest of the code using indentation.





                     l   We can use for loop inside while loop and vice versa.
                     l   We do have concept of for-else loop in Python.


                  Example 6: ‘for’ loop
                    # List of numbers
                    numbers = [ 6,5 ,3,8 ,4 ,2,5 ,4 ,11]
                    # V ariable to store the sum
                    sum = 0
                    # Iterate over the list
                    for val in numbers :
                      sum = sum+val
                    # Output: The sum is 4 8
                    print("The sum is", sum)

                  Output:

                    The sum is 48
                  Description:

                  In the above program, a list of numbers are created.  sing Loop, sum of all items in the list have
                  been calculated.

                  While Loop

                  The  while  loop in Python  is used to iterate  over a block of code as long as the  test expression
                  (condition) is true. We generally use this loop when we don’t know beforehand, the number of times
                  the loop will iterate.

                  Syntax:
                     while Condition1:
                      Statement1
                      Statement2
                      . . . . . . . . . .

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