Python: Find the missing numbers between the two sets

Last update on April 21 2025 13:04:38 (UTC/GMT +8 hours)

25. Find Missing Numbers Between Two Sets

Given two sets of numbers, write a Python program to find the missing numbers in the second set as compared to the first and vice versa. Use the Python set.

Sample Solution:

Python Code:

# Define a function 'missing_numbers' that takes two sets 'set_nums1' and 'set_nums2' as input.
def missing_numbers(set_nums1, set_nums2):
    # Use set operations to find missing numbers in both sets:
    # 1. 'set_nums1 - set_nums2' finds numbers in 'set_nums1' that are not in 'set_nums2'.
    # 2. 'set_nums2 - set_nums1' finds numbers in 'set_nums2' that are not in 'set_nums1'.
    return set(set_nums1) - set(set_nums2), set(set_nums2) - set(set_nums1)

# Define two sets of numbers 'set_nums1' and 'set_nums2' for testing.
set_nums1 = {1, 2, 3, 4, 5, 6}
set_nums2 = {3, 4, 5, 6, 7, 8}

# Call the 'missing_numbers' function and store the result in 'result'.
result = missing_numbers(set_nums1, set_nums2)

# Print the original sets and the missing numbers in both directions.
print("Original sets:")
print(set_nums1)
print(set_nums2)
print("Missing numbers in the second set as compared to the first:")
print(result[0])
print("Missing numbers in the first set as compared to the second:")
print(result[1])

# Repeat the process for a different set of sets.
set_nums1 = {1, 2, 3, 4, 5}
set_nums2 = {6, 7, 8}
result = missing_numbers(set_nums1, set_nums2)

# Print the original sets and the missing numbers in both directions.
print("\nOriginal sets:")
print(set_nums1)
print(set_nums2)
print("Missing numbers in the second set as compared to the first:")
print(result[0])
print("Missing numbers in the first set as compared to the second:")
print(result[1])

Sample Output:

Original sets:
{1, 2, 3, 4, 5, 6}
{3, 4, 5, 6, 7, 8}
Missing numbers in the second set as compared to the first:
{1, 2}
Missing numbers in the first set as compared to the second:
{8, 7}

Original sets:
{1, 2, 3, 4, 5}
{8, 6, 7}
Missing numbers in the second set as compared to the first:
{1, 2, 3, 4, 5}
Missing numbers in the first set as compared to the second:
{8, 6, 7}

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to compare two sets of numbers and print the numbers missing in each relative to the other.
Write a Python program to use set difference to determine the missing elements from one set compared to another.
Write a Python program to implement a function that takes two sets and returns a tuple of the differences.
Write a Python program to merge two sets and then output the missing numbers from each original set compared to the merged set.

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