Python: Check if a set is a subset of another set

Python sets: Exercise-10 with Solution

Write a Python program to check if a set is a subset of another set.

From Wikipedia,
In mathematics, a set A is a subset of a set B if all elements of A are also elements of B; B is then a superset of A. It is possible for A and B to be equal; if they are unequal, then A is a proper subset of B. The relationship of one set being a subset of another is called inclusion (or sometimes containment). A is a subset of B may also be expressed as B includes (or contains) A or A is included (or contained) in B.

Sample Solution:

Python Code:

print("Check if a set is a subset of another set, using comparison operators and issubset():\n")
setx = set(["apple", "mango"])
sety = set(["mango", "orange"])
setz = set(["mango"])
print("x: ",setx)
print("y: ",sety)
print("z: ",setz,"\n")
print("If x is subset of y")
print(setx <= sety)
print(setx.issubset(sety))
print("If y is subset of x")
print(sety <= setx)
print(sety.issubset(setx))
print("\nIf y is subset of z")
print(sety <= setz)
print(sety.issubset(setz))
print("If z is subset of y")
print(setz <= sety)
print(setz.issubset(sety))

Sample Output:

Check if a set is a subset of another set, using comparison operators and issubset():

x:  {'mango', 'apple'}
y:  {'mango', 'orange'}
z:  {'mango'} 

If x is subset of y
False
False
If y is subset of x
False
False

If y is subset of z
False
False
If z is subset of y
True
True

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