Python Data Structures and Algorithms - Recursion: Sum of a list of numbers

Last update on March 27 2025 12:50:21 (UTC/GMT +8 hours)

1. Sum of List Using Recursion

Write a Python program to calculate the sum of a list of numbers using recursion.

Sample Solution:

Python Code:

# Define a function named list_sum that takes a list of numbers as input
def list_sum(num_List):
    # Check if the length of the input list is 1
    if len(num_List) == 1:
        # If the list has only one element, return that element
        return num_List[0]
    else:
        # If the list has more than one element, return the sum of the first element
        # and the result of recursively calling the list_sum function on the rest of the list
        return num_List[0] + list_sum(num_List[1:])

# Print the result of calling the list_sum function with the input [2, 4, 5, 6, 7]
print(list_sum([2, 4, 5, 6, 7]))

Sample Output:

24

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to recursively compute the sum of numbers in a list using slicing.
• Write a Python program to implement tail recursion to sum a list of integers without using loops.
• Write a Python program to calculate the sum of a list of numbers recursively and print each intermediate sum.
• Write a Python program to recursively reduce a list by summing its first element with the sum of the remaining elements.

Python Code Editor:

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