Page 230 - Computer Science Class 11 Without Functions
P. 230

C.  Fill in the blanks.
           1.   The _______ block of the loop is executed when all the iterations of the loop have been executed.
           2.  In a for loop, the _______ variable keeps track of the number of times the body of the loop has been executed.
           3.   The _______ statement terminates the execution of the loop.
           4.   In the case of a nested loop, the _______ loop will iterate over the next element in the sequence only after all iterations of
              the _______ loop have been executed.
           5.  If in a program, the test condition of a loop does not evaluate to False at all, then such a loop is called _______ loop.
           6.  The _______ statement is an empty statement in Python.
        D.  Answer the following questions:
           1.  Define iteration.
         Ans:  The repetition of statements is called iteration.
           2.  Identify the test expression from the following code:
              num=2
              while num<=10:
                    print(num)
                    num=num+1
         Ans:  num<=10
           3.  Name the essential components of any loop.
         Ans:  Sequence which may be a list, string, tuple or dictionary.
              A control variable is a variable that takes the values in the sequence one by one.

              Body of the loop.
           4.  Consider the following code snippet and determine the number of times print('In Loop')is executed:
              counter = 10
              while (counter < 20):
                  print('In Loop')
                  counter = counter - 10
              else:
                  print(counter)
         Ans:  Infinite Loop. In Loop is printed infinite times.
           5.  What will be the output produced on execution of the following code snippet?
              (i) sweet='ice cream'
                for ch in sweet:
                  if ch in sweet:
                      print(ch, end='')
         Ans:  ice cream
              (ii) sweet='ice cream'
                for ch in sweet:
                    if ch in 'abcdefghijklmnopqrstuvwxyz':
                        print(ch, end='')
                print()
         Ans:  icecream
              (iii) sweet='ice cream'
                for ch in sweet:
                    if ch not in 'abcdefghijklmnopqrstuvwxyz':
                        pass
                    print(ch, end='')


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