Dictionaries Manipulation Practice

Dictionaries Manipulation Practice

Question:
Write a program to print the worker’s informations (Name age, salary) in records format.
Answer:
Employees = {‘Rohan’ : {‘age’ : 20, ‘salary’ : 10000}, ‘Mohan’ : {‘age’ : 30, ‘salary’ : 15000}}
for key in Employees :
    print “Employee”, key + ‘:’
    print ‘Age :’ + str (Employees [key] [‘age’]
    print ‘Salary :’ + str (Employees [key] [‘salary’])

Question:
What is a key-value pair with reference to Python dictionary ?
Answer:
A dictionary is a mapping between a set of indices (which are called keys) and a set of values. Each key maps a value. The association of a key and a value is called a key-value pair.

Question:
What are the characteristics of Python Dictionaries ?
Answer:
The 3 main characteristics of a dictionary are :

1.    Dictionaries are Unordered : The dictionary elements (key-value pairs) are not in ordered form.

2.    Dictionary Keys are Case Sensitive : The same key name but with different case are treated as different keys in Python dictionaries.

3.    No duplicate key is allowed : When duplicate keys encountered during assignment, the last assignment wins.

4.    Keys must be immutable : We can use strings, numbers or tuples as dictionary keys but something like [‘key’] is not allowed.

Question:
Write a Python program to input ‘n’ names and phone numbers to store it in a dictionary and to input any name and to print the phone number of the particular name.
Answer:
phonebook = dict( )

n = int(input("Enter total number of friends"))

i = 1

while i<=n:

    a = input("Enter name")

    b = input("Enter phone number")

    phonebook[a] = b

    i = i + 1

print("Dictionary is:- ")

print(phonebook)

name = input("Enter name to search")

if name in phonebook.keys():

        print("Phone number =", phonebook[name])

else:

    print("Given name not exist")