Return true if input is a Prime number

Scene 34 of Dynamic Programming in Core Technical Interview Questions for Software Engineers

By Amin Ariana — November 2013

You are given n, a positive integer. Return true if n is a prime number, and false if it's not.

Contents

Problem Statement

Evaluation

Solution

References

Problem Statement

You are given n, a positive integer. Return true if n is a prime number, and false if it's not.

Evaluation

Correct idea: 25%

Answer with no bugs: 25%

Square Root optimization: 25%

Memoization suggestion: 25%

Solution

My one liner solution in Ruby without memoization:

Testing:

References

Asked by Noah Kindler. Video http://vimeo.com/79718197 , his blog: http://www.codewod.com/ .