DICTIONARY DATA OPERATIONS:
===========================
WHAT IS DICTIONARY:
==================
STRING, LIST, TUPLE, SET ==> GROUP OF ELEMENTS 
'123', [1,2,3,4], (1,2,3,4), {1,2,3,4}
DICTIONARY IS A COLLECTION OF ITEMS
	ITEMS ==> COMBINATION OF KEY AND VALUE PAIR
	Syntax:
		key : value
CAN DEFINE WITH {}
Syntax:
	Identifier for dictionary object = {key1:value1,key2:value2,key3:value3}

Dictionary Properties:
======================
1) It is a collection of key and value pairs
2) It is an inbuilt datatype
	predefined class: dict
		type()
3) Keys in a dictionary with any datatype.
4) Values in a dictionary with any datatype.
Note: Keys in a dictionary always be with primitive datatypes.
if collection data as key in a dictionary ==> Type Error.
5) To access the dictionary values, we can use "keys".
Syntax:
	dictionary-object-name[key-name]
6) If indexing can use to access the data of dictionary ==> "Key error".
If that specified index is not as a key in a dictionary.
7) Can be ordered.
8) Dictionary can be homogeneous and heterogeneous also.
homogeneous ==>
	when keys with same type
	and values with same type
heterogeneous
	when keys ==> different type
	values ==> different type
9) Mutable datatype.
10) Keys are cannot be duplicated.
11) Values can be duplicated.

# dictionary properties

d1 = {}     # empty dictionary
d2 = {1,2,3,4}
d3 = {11:True, 12 : False, 13 : 112233}
d4 = {'a' : 11, 'b' : 12, 'c' : 13}
d5 = {'abc' : {1,2,3},'def' : [2,3,4],'ghi' : (9,7,8,6)}
# d6 = {[1,2,3] : 'a',(1,4,7) : 1122,{1,3,5} : 'pqrs'}
d6 = {1 : 10,2 : 20,3 :30}
d7 = {True:11,'a' : 13,1-2j : 15}   # Heterogeneous
d8 = {'a' : 11,'b' : 111, 'c' : 1111}   # Homogeneous


print(type(d1));print(type(d2));print(type(d3),type(d4),type(d5))
print(d1);print(d2);print(d3);print(d4);print(d5)

# values with keys
print(d3[12]);print(d4['b']);print(d5['ghi'])
print(d6[1]);print(d6[2])
# print(d6[-1])
print(d6)
print(type(d7));print(type(d8))

print(d8)
print(id(d8))

d8['c'] = 9797

print(d8)
print(id(d8))

d8['p'] = 112233

print(d8)
print(id(d8))

=============================================

Creation of Dictionary data:
============================
1) Compile time definition:
===========================
==> direct value assignment method
Syntax:
	dictionary-object-name = {key1:value1,key2:value2,...}

# Compile Time Definition of the dictionary

d1 = {'a' : 100,'b' : 200, 'c' : 300,'b' : 500,'d' : 300}

print(d1)
print(type(d1))

============================================================

2) Run Time definition:
=======================
eval() ==> can use.
==> this definition can dynamically changed.

Syntax:
	dictionary-object-name = eval(input("Enter a dictionary data:"))

# Run Time Definition of the Dictionary

d1 = eval(input("Enter a dictionary data:"))

print(type(d1))
print(d1)

============================================
3) using dict()
===============
Syntax:
	dictionary-name = dict({key1:value1,key2:value2})

# using dict() method

d1 = dict() # empty dictionary
d2 = dict({'a' : 11,'b' : 22,'c' : 33})
# d3 = dict((1,3,5,7,9))

print(type(d1));print(type(d2))
print(d1);print(d2)

============================================================
Traversing on Dictionary:
=========================

# WAP TO ENTER NAME AND PERCENTAGE IN A DICTIONARY AND DISPLAY THAT INFORMATION.

record = dict()     # created an empty dictionary

count = int(input("Enter the size of the class:"))

i = 1   # initialization

while i <= count:
    name = input("Enter a student name:")
    marks = input("Enter student's percentage:")
    record[name] = marks
    i += 1

print("Name of the Student","\t","% of marks of the Student")
for data in record:
    print("\t\t",data,"\t\t\t\t\t",record[data])

==============================================================
Delete data from dictionary data:
=================================
1) using del property:
======================

# delete operation

d1 = {'abc' : 111, 'def' : 222, 'ghi' : 333, 'jkl' : 444}

# del property can use to delete the value of the dictionary with 'key
# Syntax: del dict-name[key]

print("Before The Delete Operation:",d1)

del d1['ghi']

print("After The Delete Operation:",d1)

# we can delete the whole dictionary permanently.

del d1

# print(d1)

=======================================

2) clear()
=========
it can use to delete/remove the whole dictionary.

Syntax:
	dict-name.clear()

# clear() Method

d1 = {'abc' : 111, 'def' : 222, 'ghi' : 333, 'jkl' : 444}

print("The Dictionary before the delete operation:",d1)

d1.clear()

print("The Dictionary after the delete operation:",d1)

======================================

3) pop()
========
we can use to remove the value of the dictionary which is associated with the specified key.
Syntax:
	dict-name.pop(key)

Note:
====
if the specified key is not in the dictionary ==> Key Error

# pop() method

d1 = {'abc' : 111, 'def' : 222, 'ghi' : 333, 'jkl' : 444}

print("Before the pop operation:",d1)

d1.pop('ghi')
# d1.pop('pqr')     Key Error

print("After the pop operation:",d1)

=====================================================

5) popitem()
============
it can use to remove an arbitrary item {key and value} from the last of the dictionary.

Syntax:
	dict-name.popitem()

# popitem()

d1 = {'abc' : 111, 'def' : 222, 'ghi' : 333, 'jkl' : 444}

print("The Dictionary before the pop operation is: ",d1)

d1.popitem()
d1.popitem()

print("The Dictionary after the pop operation is: ",d1)
	

===============