Prime number test

Question

Let me know a better way to check whether a number is prime or not.
https://code.sololearn.com/cgCjY1UDVzWO/?ref=app

Answer 1

You don't need to check all the way up to x. If x isn't divisible by any number up to sqrt(x)+1, it is a prime number.

Also, you don't need to check every single possible divisor. You can check if x is divisible by 2 or 3 and then go from 3 up to sqrt(x) in steps of 2.

Answer 2

https://code.sololearn.com/cIq5PZ7yhZlQ/?ref=app

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