Chapter 6 of baabtra littleCoder Program

1. Little Coder Program
by

2. What you’ve learned?
How to compare conditions using if statements
What is block statements and importance of keeping equal spacing for
block statements
How to give else conditions
How to nest more than one If and else conditions
How to give multiple conditions inside the same if condition

3. LoopsChapter 6

4. Back to Anna !
• Do you remember this particular pink color block that you’ve used
for anna?
• We’ve used it whenever we wanted Anna to perform the same
instruction repeatedly. Similarly in python we use loops to repeat
some particular instructions

5. Loops
• That is, whenever you want a computer to repeat something over
and over again a loop instruction can be used. A loop is used to
make a computer do something more than one time.

6. Why Loops?
• Nothing is worse than having to do the same thing over and over
again. For example To print hello five times in Python, you could
do the following:
>>> print("hello")
hello
>>> print("hello")
hello
>>> print("hello")
hello
>>> print("hello")
hello
>>> print("hello")
hello

7. “It’s not tideous !! Rather we can try with loop as below
which is much neater”
>>> for x in range(0, 5):
print('hello')
hello
hello
hello
hello
hello

8. “It’s not tideous !! Rather we can try with loop as below
which is much neater”
>>> for x in range(0, 5):
print('hello')
hello
hello
hello
hello
hello
The range function can be used to create a
list of numbers with in a range
For example
>>>print(list(range(10, 20)))
[10, 11, 12, 13, 14, 15, 16, 17, 18, 19]

9. Example
>>> for x in range(0, 5):
print('hello %s' % x)

10. Example
>>> for x in range(0, 5):
print('hello %s' % x)
Range(0,5) will return a list
of numbers from 0 to 5 as
below
[0,1,2,3,4,5]

11. Example
>>> for x in range(0, 5):
print('hello %s' % x)
[0,1,2,3,4,5]
x
x is a variable which will
have value 0 when the loop
executes for the first time.

12. Example
>>> for x in range(0, 5):
print('hello %s' % x)
[0,1,2,3,4,5]
x
Output
hello 0
1st Iteration

13. Example
>>> for x in range(0, 5):
print('hello %s' % x)
[0,1,2,3,4,5]
x
Output
hello 0
hello 1
2nd Iteration

14. Example
>>> for x in range(0, 5):
print('hello %s' % x)
[0,1,2,3,4,5]
x
Output
hello 0
hello 1
hello 2
3rd Iteration

15. Example
>>> for x in range(0, 5):
print('hello %s' % x)
[0,1,2,3,4,5]
x
Output
hello 0
hello 1
hello 2
hello 3
4th Iteration

16. Example
>>> for x in range(0, 5):
print('hello %s' % x)
[0,1,2,3,4,5]
x
Output
hello 0
hello 1
hello 2
hello 3
hello 4
5th Iteration

17. Example
>>> for x in range(0, 5):
print('hello %s' % x)
[0,1,2,3,4,5]
x
Output
hello 0
hello 1
hello 2
hello 3
hello 4
hello 5
6th Iteration

18. Loop with lists
Fruits=[‘orange’,’apple’,’grape’,’pappaya’,’banana’]
for i in fruits:
print(i)
Here we have
created a list
variable named
fruits

19. Loop with lists
Fruits=[‘orange’,’apple’,’grape’,’pappaya’,’banana’]
for i in fruits:
print(i)
Now we are using
the variable fruits
instead of calling
range() function.

20. Loop with lists
Fruits=[‘orange’,’apple’,’grape’,’pappaya’,’banana’]
for i in fruits:
print(i)
Output
Orange
Apple
Grape
Pappaya
banana

21. While Loop

22. While loop
• A for loop isn’t the only kind of loop you can make in Python.
There’s also the while loop. A for loop is a loop of a specific
length, whereas a while loop is a loop that is used when you don’t
know ahead of time when it needs to stop looping.
>>> x = 45
>>> y = 80
>>> while x < 50 and y < 100:
x = x + 1
y = y + 1
print(x, y)

23. Exercise !

24. Exercise !
• Print all the numbers between 350 and 450 using for loop
• Print all the even numbers below 100 using while loop
• Print all the odd numbers between 100 and 200 using while loop

25. End of Chapter 6