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Print All Armstrong Numbers in a Given Range

Certification: Basic Level Accuracy: 67.31% Submissions: 52 Points: 10

Write a Python program that finds all Armstrong numbers in a given range.

Example 1
    

  • Input: start = 100, end = 1000
    • 

  • Output: [153, 370, 371, 407]
    • 

  • Explanation: 

      

    • Step 1: For each number in the range [100, 1000], check if it's an Armstrong number.
      • 

    • Step 2: For 153: 1³ + 5³ + 3³ = 1 + 125 + 27 = 153 ✓
      • 

    • Step 3: For 370: 3³ + 7³ + 0³ = 27 + 343 + 0 = 370 ✓
      • 

    • Step 4: For 371: 3³ + 7³ + 1³ = 27 + 343 + 1 = 371 ✓
      • 

    • Step 5: For 407: 4³ + 0³ + 7³ = 64 + 0 + 343 = 407 ✓
      • 

    • Step 6: No other Armstrong numbers exist in this range.
      • 

    

    •
Example 2
    

  • Input: start = 1, end = 10
    • 

  • Output: [1, 2, 3, 4, 5, 6, 7, 8, 9]
    • 

  • Explanation: 

      

    • Step 1: For single-digit numbers, each number is an Armstrong number.
      • 

    • Step 2: For example, 9: 9¹ = 9 ✓
      • 

    • Step 3: All numbers from 1 to 9 are Armstrong numbers.
      • 

    

    •
Constraints
    

  • 1 ≤ start ≤ end ≤ 10^6
    • 

  • Time Complexity: O(n * log(n))
    • 

  • Space Complexity: O(k) where k is the number of Armstrong numbers found
    •
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Hint
Solution

Solution Hints

    
  
  • Calculate the number of digits in each number
    • 
  
  • Use a loop to extract each digit and compute the sum of powers
    •

The following are the steps to solve: 

    

  •  Define a function that accepts a range (start, end).
    • 

  •  Iterate through each number in that range.
    • 

  • Convert the number to digits (ex: 153 : [1, 5, 3]).
    • 

  •  Find the number of digits (this becomes the power).
    • 

  •  Calculate the sum of each digit raised to the power.
    • 

  • Check if the sum equals the original number.
    • 

  • If yes, it is an Armstrong number, add it to the result list.
    • 

  • Return the final list of Armstrong numbers.
    •

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