Page 311 - Computer Science V2.0 Class 11

11.4.4 More Examples of while Statement
In Table 11.3, we give some more examples of the while loop.
Table 11.3: Examples of while loop

Statements Output Explanation

i = 1 123456 As the value of i becomes 7, the condition
while i <= 6: evaluates to False and the loop terminates.
print(i, end='') The int objects are displayed one after the
i += 1 other without any spaces as end=''.
i = 1 sum: 55 As the value of i becomes 11, the loop
count = 0 terminates and the statement in the else
while i<=10: block is executed.
count=count+i
i =i +1
else:
print('sum:', count)
n = 8 64 36 16 4 As long as the test condition, n>0 is True,
while n > 0: Done the statements in the body of the while loop
print(n*n, end=' ') will be executed. After the loop terminates
normally (without a break statement), the
n = n-2
statement in the else block print("\nDone")
else:
gets executed.
print('\nDone')

In the case of a while loop, the test condition is checked at the entry point of the loop. So, the loop may not be
executed even once, if the test condition is False. Therefore, always remember to initialize the control variable
before the loop begins. If the initial value is not given to the control variable, the while loop will not execute.
Secondly, the control variable has to be updated inside the while loop, otherwise, the loop will never terminate and
become an infinite loop.

1. Consider the code given below:
for num in range(10,30,3):
print(num-1)
Identify the following components of the given loop:
a. Control variable
b. Initial value of control variable

c. Final value of control variable
d. Step Value
e. Body of loop
2. Is the following code elegant? If not, rewrite it to make it more elegant:
num = 10
while(num<30):
print(num-1, end = ' ')

num = num+3

Looping in Python 297