Python: Reads n digits chosen from 0 to 9 and prints the number of combinations where the sum of the digits equals to another given number(s)

Last update on April 17 2025 13:05:46 (UTC/GMT +8 hours)

Sum of Digit Combinations

Write a Python program that reads n digits (given) chosen from 0 to 9 and prints the number of combinations where the sum of the digits equals another given number (s). Do not use the same digits in a combination.

Input:
Two integers as number of combinations and their sum by a single space in a line. Input 0 0 to exit.

Sample Solution:

Python Code:

# Import the 'itertools' module
import itertools

# Prompt the user to input the number of combinations and sum, input 0 0 to exit
print("Input number of combinations and sum, input 0 0 to exit:")

# Infinite loop for continuous input until the user enters 0 0
while True:
    # Take user input for the number of combinations and sum, and convert to integers
    x, y = map(int, input().split())

    # Check if the user wants to exit the loop
    if x == 0 and y == 0:
        break

    # Generate all combinations of 'x' elements from the range 0 to 9
    s = list(itertools.combinations(range(10), x))

    # Initialize a counter variable to count the valid combinations
    ctr = 0

    # Iterate through each combination
    for i in s:
        # Check if the sum of the current combination is equal to the target sum 'y'
        if sum(i) == y:
            ctr += 1

# Print the total count of valid combinations
print(ctr)

Sample Output:

Input number of combinations and sum, input 0 0 to exit:
 5 6
 2 4
 0 0
2

Explanation:

Here is a breakdown of the above Python code:

First the code imports the 'itertools' module.
It prompts the user to input the number of combinations and sum, with the option to input 0 0 to exit.
The code enters an infinite loop to continuously take input until the user enters 0 0.
User input for the number of combinations and sum is taken and converted to integers.
It generates all combinations of 'x' elements from the range 0 to 9.
The code iterates through each combination, checking if the sum equals the target sum 'y'.
The total count of valid combinations is printed after exiting the loop.

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to count the combinations of n digits where the product equals a given number without reusing digits.
Write a Python program to generate all unique permutations of n digits that sum to a given target.
Write a Python program to partition a set of digits into two groups that have equal sums.
Write a Python program to determine the maximum sum achievable by combining a set of given digits in any order.

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Python Code Editor:

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