Page 213 - Computer Science Class 11 Without Functions
P. 213

4 10
                 5 10
            Note that the range() function returns an immutable sequence of values and that the control variable i takes values
            from this sequence. So, changing the value of the control variable in the body of the for statement does not change
            the flow of execution of the for statement.

            9.3.4 More Examples of for Statement

            In Table 9.2, we give some more examples of the use of the for statement:
                                                 Table 9.2: Statements using for loop

                           Statements                        Output                        Explanation

             for ch in 'ABCD':                        A                      The control variable ch takes  each value in
                 print(ch)                            B                      the sequence of characters: 'A', 'B',
                                                                             'C', 'D'
                                                      C
                                                      D

             numbers = [9, 0, -4, 23, 17, 56] 0                              The control variable n takes values in the
             for n in numbers:                        -4                     list numbers, one by one. For each value
                                                                             of the control variable,  n,  from the list
                 if n%2 == 0:                         56
                                                                             numbers, print statement is executed if
                    print(n)                          Job Done
                                                                             n%2 == 0. The statement print('Job
             print('Job Done')                                               Done') is not part of the body of the loop,
                                                                             so it is executed after the loop terminates.
             for x in range(30, 50, 5):               30                     The control variable, x, takes values in the

                 print(x)                             35                     range of 30 to 50 (excluding 50) in steps of
                                                                             5.
                                                      40
                                                      45
             for p in range(4):                       0 1 2 3                The control variable p takes values in the

                print(p, end=' ')                                            sequence 0, 1, 2, 3. The default start value is 0.
             for p in range(100, 90, -2):             100 98 96 94 92  As the body of the for loop is executed,
                print(p, end=' ')                     BYE                    the numbers in the range of 100 to 91 (in
                                                                             steps of -2) are printed. The else part of
             else:
                                                                             the for loop is executed after all iterations
                print("BYE")
                                                                             of the loop have been executed.
             for c in 'ROSE':                         Good Code              For each value  of the control  variable  c
                 if c == 'O':                         O                      in  the string  'ROSE',  the  if-else
                                                                             statement is executed.
                     print(c)                         Good Code
                 else:                                Good Code
                     print('Good Code')
             for c in 'ROSE':                         O                      For each value of the control variable c in

                 if c == 'O':                         Good Code              the string  'ROSE' the  if statement is
                                                                             executed. The else clause is part of the
                     print(c)
                                                                             for statement, and it  is executed after all
             else:
                                                                             iterations of the for statement have been
                 print('Good Code')
                                                                             completed.



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