Set datatypes in python

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SET DATATYPE
Sets are used to store multiple items in a single variable and it is
Mutable.
Set is a collection which is unordered, unchangeable*, unindexed and
Every item is unique (No duplicate items).
Use set when we don’t want duplicate values in our data.
Set items can be of any data type
Create a Set:
Sets are written with curly brackets { } and every element in set is
separated by comma,
Syntax: set_name={value1,value2,value3,…}
Set doesn’t support indexing & slicing because it is not a
sequence data type.
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Sets are unordered, so you cannot be sure in which order the
items will appear.
Set items can appear in a different order every time you use
them, and cannot be referred to by index or key.
Set items are unchangeable, meaning that we cannot change
the items after the set has been created.
Once a set is created, you cannot change its items, but you can
remove items and add new items.
Sets cannot have two items with the same value.
Set stores only immutable datatypes.
Sets can be used to perform mathematical set operations like
union ,intersection , difference etc

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General-purpose built-in functions that are commonly used with sets:
1. len(s): Returns the number of elements in sets.
2. max(s): Returns the largest element in sets.
3. min(s): Returns the smallest element in sets.
4. sorted(s): Returns a new sorted list from the elements in sets.
5. sum(s): Returns the sum of all elements in set s, if they are
numbers.
6. any(s): Returns True if any element in the set s is true. If the set
is empty, returns False.
7. all(s): Returns True if all elements in the set s are true or if the
set is empty.
8. Set() : To create a set

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SET METHODS:
1. add() : add an element to a set
2. pop() :Remove first element and return
3. remove() ; Remove specified element
4. discard() : Remove specified element
5. clear() ; Remove all elements from a set
6. copy() : Return a copy of a set
7. union() : Return a set containing the union of sets
8. update() : update the set with another set
9. difference() : Return the difference of two sets as a new set
10.intersection(); Return the intersection of two sets as a new set
syntax for set methods is
set_name.add()

5. Creating Sets
# Empty set
s1 = set()
# Set with integers
s2 = {1, 2, 3, 4}
# Set with mixed data types
s3 = {10, "apple", 3.14, True}
# Duplicates are automatically removed
s4 = {1, 2, 2, 3, 4, 4}
print(s4) # {1, 2, 3, 4}

6. Accessing Set Elements
s = {"apple", "banana", "cherry"}
for item in s:
print(item)

7. Adding & Removing Elements
s = {1, 2, 3}
# Add element
s.add(4)
print(s) # {1, 2, 3, 4}
# Add multiple elements
s.update([5, 6])
print(s) # {1, 2, 3, 4, 5, 6}
# Remove element (gives error if not found)
s.remove(2)
print(s) # {1, 3, 4, 5, 6}

8. Set Operations
a = {1, 2, 3, 4}
b = {3, 4, 5, 6}
print(a | b) # Union → {1, 2, 3, 4, 5, 6}
print(a & b) # Intersection → {3, 4}
print(a - b) # Difference → {1, 2}
print(a ^ b) # Symmetric Difference → {1, 2, 5, 6}
# Discard element (no error if not found)
s.discard(10)
# Pop random element
print(s.pop()) # Removes a random item

9. Set Methods
s = {1, 2, 3}
print(len(s)) # 3
print(2 in s) # True
print(s.issubset({1,2,3,4})) # True
print(s.issuperset({1,2})) # True
print(s.isdisjoint({4,5})) #True

10. Real-Life Example – Removing Duplicates
nums = [1, 2, 2, 3, 4, 4, 5]
unique_nums = set(nums)
print(unique_nums) # {1, 2, 3, 4, 5}