Python: Print out a set containing all the colors from a list which are not present in other list

Python Basic: Exercise-29 with Solution

Unique Colors Finder

Write a Python program that prints out all colors from color_list_1 that are not present in color_list_2.

Test Data:
color_list_1 = set(["White", "Black", "Red"])
color_list_2 = set(["Red", "Green"])
Expected Output :
{'Black', 'White'}

Pictorial Presentation:

Sample Solution-1:

Python Code:

# Create two sets, color_list_1 and color_list_2.
color_list_1 = set(["White", "Black", "Red"])
color_list_2 = set(["Red", "Green"])

# Print the original elements of the sets.
print("Original set elements:")
print(color_list_1)
print(color_list_2)

# Calculate and print the difference of color_list_1 and color_list_2.
print("\nDifference of color_list_1 and color_list_2:")
print(color_list_1.difference(color_list_2))

# Calculate and print the difference of color_list_2 and color_list_1.
print("\nDifference of color_list_2 and color_list_1:")
print(color_list_2.difference(color_list_1))

Sample Output:

Original set elements:
{'White', 'Black', 'Red'}
{'Green', 'Red'}

Differenct of color_list_1 and color_list_2:
{'White', 'Black'}

Differenct of color_list_2 and color_list_1:
{'Green'}

Explanation:

The said code defines two sets called "color_list_1" and "color_list_2" containing string elements.

The elements of both sets are then printed.

After that, it uses the difference() method on "color_list_1" and passes "color_list_2" as an argument to it. This method returns the elements that are in the "color_list_1" but not in "color_list_2".

Again it uses the difference() method on "color_list_2" and passes "color_list_1" as an argument to it. This method returns the elements that are in the "color_list_2" but not in "color_list_1".

The output of the code will be:

Original set elements:

{'Red', 'White', 'Black'}

{'Red', 'Green'}

Differenct of color_list_1 and color_list_2:

{'White', 'Black'}

Differenct of color_list_2 and color_list_1:

{'Green'}

Sample Solution-2:

Python Code:

# Create two sets, color_list_1 and color_list_2.
color_list_1 = set(["White", "Black", "Red"])
color_list_2 = set(["Red", "Green"])

# Print the original elements of the sets.
print("Original set elements:")
print(color_list_1)
print(color_list_2)

# Calculate and print the difference of color_list_1 and color_list_2 using set difference (-) operator.
print("\nDifference of color_list_1 and color_list_2:")
print(color_list_1 - color_list_2)

# Calculate and print the difference of color_list_2 and color_list_1 using set difference (-) operator.
print("\nDifference of color_list_2 and color_list_1:")
print(color_list_2 - color_list_1)

Sample Output:

Original set elements:
{'Red', 'Black', 'White'}
{'Red', 'Green'}

Differenct of color_list_1 and color_list_2:
{'Black', 'White'}

Differenct of color_list_2 and color_list_1:
{'Green'}

Explanation:

The said code defines two sets, "color_list_1" and "color_list_2", with the initial elements "White", "Black", "Red" and "Red", "Green" respectively.

It then prints the original sets, followed by the difference between color_list_1 and color_list_2 (the elements in color_list_1 that are not in color_list_2) and the difference between color_list_2 and color_list_1 (the elements in color_list_2 that are not in color_list_1).

Here the "-" operator is used to get the difference between two sets.

Python Code Editor:

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