# Thursday Code Puzzler: Is This An Armstrong Number?

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Thursday is code puzzler day here at DZone. The idea is simple: solve the coding problem as efficiently as you can, in any language or framework that you find suitable.

*Note: Even though there really is nothing stopping you from finding a solution to this on the internet, try to keep honest, and come up with your own answer. It's all about the participation!*

Do you have code puzzlers that you'd like to share with the DZone community? If so, please submit here.

**Determine if a given number is an Armstrong number**

Write a method that will return true if the number passed through as a parameter is an Armstrong number, as defined in Wikipedia . Numbers satisfy this condition if the number is a sum of it's own digits, each raised to the power of the number of digits.

For example, 153 has 3 digits, so everything is raised to the power of 3.

153 = 1^{ to the power of 3} + 5^{ }*to the power of 3* + 3^{ }*to the power of 3*

**Given a single linked list, write a method that will determine if the "next" pointer of one of the nodes is pointing to a previous node in your list. **

Catch up on all our previous puzzlers here.

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