Python: Union of sets
Write a Python program to create a union of sets.
From Wikipedia,
In set theory, the union (denoted by ∪) of a collection of sets is the set of all elements in the collection. It is one of the fundamental operations through which sets can be combined and related to each other. A nullary union refers to a union of zero (0) sets and it is by definition equal to the empty set.
The union of two sets A and B is the set of elements which are in A, in B, or in both A and B. In symbols,
A ∪ B = {x : x ∈ A or x ∈ B}
For example, if A = {1, 3, 5, 7} and B = {1, 2, 4, 6, 7} then A ∪ B = {1, 2, 3, 4, 5, 6, 7}. A more elaborate example (involving two infinite sets) is:
A = {x is an even integer larger than 1}
B = {x is an odd integer larger than 1}
A ∪ B = {2,3,4,5,6,...}
As another example, the number 9 is not contained in the union of the set of prime numbers {2, 3, 5, 7, 11, ...} and the set of even numbers {2, 4, 6, 8, 10, ...}, because 9 is neither prime nor even.
Sets cannot have duplicate elements, so the union of the sets {1, 2, 3} and {2, 3, 4} is {1, 2, 3, 4}. Multiple occurrences of identical elements have no effect on the cardinality of a set or its contents.
Visual Presentation:
Sample Solution-1:
Using union() function
Python Code:
Sample Output:
Original sets: {'blue', 'green'} {'blue', 'yellow'} Union of above sets: {'blue', 'yellow', 'green'} Original sets: {1, 2, 3, 4, 5} {1, 5, 6, 7, 8, 9} Union of above sets: {1, 2, 3, 4, 5, 6, 7, 8, 9}
Sample Solution-2:
Using | operator
Python Code:
Sample Output:
Original sets: {'green', 'blue'} {'blue', 'yellow'} Union of above sets: {'green', 'yellow', 'blue'} Original sets: {1, 2, 3, 4, 5} {1, 5, 6, 7, 8, 9} Union of above sets: {1, 2, 3, 4, 5, 6, 7, 8, 9}
Sample Solution-3:
Union of more than two sets:
Python Code:
Sample Output:
Original sets: {1, 2, 3, 4, 5} {1, 5, 6, 7, 8, 9} {3, 4, 5, 9, 10} {5, 7, 9, 10, 12, 14} Union of first three sets: {1, 2, 3, 4, 5, 6, 7, 8, 9, 10} Union of above four sets: {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14}
Python Code Editor:
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