Strong Number in C

# Strong Number in C

Example

Input

```Input number: 145
```

Output

`145 is STRONG NUMBER`

## Required knowledge

### What is Strong number?

Strong number is a special number whose sum of factorial of digits is equal to the original number.
For example: 145 is strong number. Since, `1! + 4! + 5! = 145`

## Logic to check Strong number

Step by step descriptive logic to check strong number.

1. Input a number from user to check for strong number. Store this in a variable say num. Copy it to a temporary variable for calculations purposes, say `originalNum = num`.
2. Initialize another variable to store sum of factorial of digits, say `sum = 0`.
3. Find last digit of the given number num. Store the result in a variable say `lastDigit = num % 10`.
4. Find factorial of lastDigit. Store factorial in a variable say fact.
5. Add factorial to sum i.e. `sum = sum + fact`.
6. Remove last digit from num as it is not needed further.
7. Repeat steps 3 to 6 till `num > 0`.
8. After loop check condition for strong number. If `sum == originalNum`, then the given number is Strong number otherwise not.