Page 311 - AI Ver 1.0 Class 9
P. 311
Stop
Flowchart
Source Code: START
num=1
Num 1 Sum 0
sum=0
while num<6:
sum=sum+num Is No Display
Num > 6? "Sum is sum"
num=num+1
print("Sum is ",sum) Yes
Output: Sum = sum+num STOP
Sum is 15
Num = num+1
Lists in Python
List is a collection of heterogeneous data arranged in a sequence. The values can be of any data type like string,
integer, float, objects or even a list. Each value in a list is called an element and its position in a list is referred
by an index number. The number of elements in a list will make the length of a list. All the elements in a list are
separated by comma and enclosed in square brackets [ ].
List is a mutable data type in Python as the content of the list can be added, modified or deleted by the user
anytime throughout the code. A number of operations can be performed on the list by using a few built-in list
functions which we will study in detail in this chapter.
Important Features of Lists
Based on the above definition, the list has the following important features:
• It is mutable data type.
• It is an ordered sequence of values.
• Each element is separated by comma and enclosed in square brackets [ ].
• Each value/element is accessed by an index number.
• The values can be added, modified or deleted by the user throughout the program.
• It stores the values of different data types.
Creating a List
A list is created by enclosing the values within square brackets. Each value/element is separated by a comma
and stored under a common name. These values can be of different data types. The name follows the rules of
naming conventions for identifiers as shown below:
Examples Commands
Creating an empty list list1 = []
Creating a list with single value list2 = [56]
Creating a list of friends friends = ["Saisha", "Advika", "Arshia"]
Creating a list of marks marks=[92, 91, 89, 95, 93]
Introduction to Python 309

