# Thursday Code Puzzler: Circular Primes

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It's Thursday, so it's time for another code puzzler. 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!*

**Circular Primes **

A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will be prime. For example 1193 is a circular prime, since 1931, 9311 and 3119 all are also prime.

Your task is to calculate how many circular primes exist below 1 million.

Catch up on all our previous puzzlers here

The Java Zone is brought to you in partnership with ZeroTurnaround. Discover how you can skip the build and redeploy process by using JRebel by ZeroTurnaround.

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