Prime Number

Published on 16 November 2018 (Updated: 22 January 2024)

Welcome to the Prime Number page! Here, you'll find a description of the project as well as a list of sample programs written in various languages.

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A prime number is a positive integer which is divisible only by 1 and itself. For example: 2, 3, 5, 7, 11, 13

Since every number is divisible by One so, Two is the only even and the smallest prime number.


Create a file called Prime Number using the naming convention appropriate for your language of choice.

Write a sample program which accepts an integer on the command line and outputs if the integer is a Prime number or not.


Every project in the Sample Programs repo should be tested. In this section, we specify the set of tests specific to Prime Number. In order to keep things simple, we split up the testing as follows:

Prime Valid Tests

Description Input Output
Sample Input 0 "0" "composite"
Sample Input 1 "1" "composite"
Sample Input 2 "2" "prime"
Sample Input Small Composite "4" "composite"
Sample Input Small Prime "7" "prime"
Sample Input Large Composite "4011" "composite"
Sample Input Large Prime "3727" "prime"

Prime Invalid Tests

Description Input
No Input  
Empty Input ""
Invalid Input: Not A Number "a"
Invalid Input: Not An Integer "6.7"
Invalid Input: Negative "-7"

All of these tests should output the following:

Usage: please input a non-negative integer