Python Exercises: Sum of missing numbers of a list of integers

Last update on April 19 2025 12:57:32 (UTC/GMT +8 hours)

Sum Missing Numbers

Write a Python program to sum the missing numbers in a given list of integers.

Sample Data:
([0, 3, 4, 7, 9]) -> 22
([44, 45, 48]) -> 93
([-7, -5, -4, 0]) -> -12

Sample Solution-1:

Python Code:

# Define a function named 'test' that takes a list 'nums' as input.
def test(nums):
    # Find the maximum and minimum numbers in the input list 'nums'.
    max_num = max(nums)
    min_num = min(nums)
    
    # Calculate the sum of missing numbers within the range [min_num, max_num] using the formula:
    # Sum = (max + min) * (max - min + 1) // 2 - sum(nums)
    return (max_num + min_num) * (max_num - min_num + 1) // 2 - sum(nums)

# Define the original list 'nums'.
nums = [0, 3, 4, 7, 9]
print("Original list:")
print(nums)

# Call the 'test' function to calculate the sum of missing numbers in the list of integers.
print("Sum of missing numbers of the said list of integers:", test(nums))

# Define another list 'nums'.
nums = [44, 45, 48]
print("\nOriginal list:")
print(nums)

# Call the 'test' function for the second list of integers.
print("Sum of missing numbers of the said list of integers:", test(nums))

# Define another list 'nums'.
nums = [-7, -5, -4, 0]
print("\nOriginal list:")
print(nums)

# Call the 'test' function for the third list of integers.
print("Sum of missing numbers of the said list of integers:", test(nums))

Sample Output:

Original list:
[0, 3, 4, 7, 9]
Sum of missing numbers of the said list of integers:
22
Original list:
[44, 45, 48]
Sum of missing numbers of the said list of integers:
93
Original list:
[-7, -5, -4, 0]
Sum of missing numbers of the said list of integers:
-12

Flowchart:

Sample Solution-2:

Python Code:

# Define a function named 'test' that takes a list 'nums' as input.
def test(nums):
    # Find the maximum and minimum numbers in the input list 'nums'.
    max_num = max(nums)
    min_num = min(nums)
    
    # Calculate the sum of missing numbers within the range [min_num, max_num] using the formula:
    # Sum = sum(range(min_num, max_num + 1)) - sum(nums)
    return sum(range(min_num, max_num + 1)) - sum(nums)

# Define the original list 'nums'.
nums = [0, 3, 4, 7, 9]
print("Original list:")
print(nums)

# Call the 'test' function to calculate the sum of missing numbers in the list of integers.
print("Sum of missing numbers of the said list of integers:", test(nums))

# Define another list 'nums'.
nums = [44, 45, 48]
print("\nOriginal list:")
print(nums)

# Call the 'test' function for the second list of integers.
print("Sum of missing numbers of the said list of integers:", test(nums))

# Define another list 'nums'.
nums = [-7, -5, -4, 0]
print("\nOriginal list:")
print(nums)

# Call the 'test' function for the third list of integers.
print("Sum of missing numbers of the said list of integers:", test(nums))

Sample Output:

Original list:
[0, 3, 4, 7, 9]
Sum of missing numbers of the said list of integers:
22
Original list:
[44, 45, 48]
Sum of missing numbers of the said list of integers:
93
Original list:
[-7, -5, -4, 0]
Sum of missing numbers of the said list of integers:
-12

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to sum all missing numbers between the minimum and maximum values in a list.
Write a Python program to compute the sum of missing even numbers in a given list.
Write a Python program to identify missing numbers in a sorted list and return both the missing numbers and their total sum.
Write a Python program to calculate the sum of missing numbers in a list after removing duplicate entries.

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