Strong number
Detailed guide and Python implementation for the 'Strong number' problem.
Problem Statement
Write a function is_strong(n) that takes a positive integer n and returns True if it is a Strong number, or False otherwise. A Strong number is a number where the sum of the factorials of its individual digits equals the number itself. For example, 145 = 1! + 4! + 5! = 1 + 24 + 120 = 145.
- •1 <= n <= 10^6
Examples
n = 145
True
1! + 4! + 5! = 1 + 24 + 120 = 145, which equals n.
n = 2
True
2! = 2, which equals n.
n = 123
False
1! + 2! + 3! = 1 + 2 + 6 = 9, which is not 123.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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