Python Armstrong number generator: Generate next Armstrong numbers

Last update on December 21 2024 07:30:12 (UTC/GMT +8 hours)

Write a Python program to implement a generator that generates the next Armstrong number after a given number.

When the sum of the cube of the individual digits of a number is equal to that number, the number is called Armstrong number. For Example 153 is an Armstrong number because 153 = 1³+5³+3³.

Sample Solution:

Python Code:

def is_armstrong_number(n):
    num_str = str(n)
    num_len = len(num_str)
    sum_of_cubes = sum(int(digit) ** num_len for digit in num_str)
    return n == sum_of_cubes
def next_armstrong_number(start):
    while True:
        start += 1
        if is_armstrong_number(start):
            yield start

# Accept input from the user
n = int(input("Input a number: "))
# Create the generator object
armstrong_gen = next_armstrong_number(n)
# Generate and print the next Armstrong number
print("Next Armstrong number:")
for _ in range(1):
    print(next(armstrong_gen))

Sample Output:

Input a number: 370
Next Armstrong number:
371

Enter a number: 153
Next Armstrong numbers:
370

Input a number: 407
Next Armstrong number:
1634

Explanation:

In the above exercise -

The is_armstrong_number() function first checks whether a given number is an Armstrong number. The function calculates the sum of cubes of digits and compares it with the original number to determine if it's an Armstrong number.

Next, the generator function next_armstrong_number() generates the next Armstrong numbers one by one.

Flowchart:

Python Code Editor:

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