Linked Questions

13
votes
28answers
983 views

Am I a Sophie Germain prime? [duplicate]

A Sophie Germain Prime is a prime number P such that 2P+1 is prime as well. Given a prime number as input, your task is to determine whether it is a Sophie Germain Prime. Standard Input/Output rules ...
9
votes
20answers
1k views

Prime numbers between n and 2n [duplicate]

Bertrand's postulate states that there is always at least 1 prime number between n and 2n for all n greater than 1. Challenge Your task is to take a positive integer n greater than 1 and find all of ...
6
votes
15answers
830 views

Check If my String is Prime [duplicate]

We define a prime character as a character that has a prime ASCII value. We define a prime string as a String that only contains prime characters. Given a String that only contains printable ASCII, ...
-1
votes
6answers
335 views

Primes, as efficiently inefficient as possible [duplicate]

Write a program that tests if a number n is prime by checking that none of the integers between 2 and ...
431
votes
774answers
134k views

“Hello, World!”

So... uh... this is a bit embarrassing. But we don't have a plain "Hello, World!" challenge yet (despite having 35 variants tagged with hello-world, and counting). While this is not the most ...
204
votes
340answers
46k views

Golf you a quine for great good!

Using your language of choice, golf a quine. A quine is a non-empty computer program which takes no input and produces a copy of its own source code as its only output. No cheating -- that means ...
124
votes
484answers
37k views

Shortest infinite loop producing no output

Your task is to create the shortest infinite loop! The point of this challenge is to create an infinite loop producing no output, unlike its possible duplicate. The reason to this is because the code ...
150
votes
388answers
28k views

Implement a Truth-Machine

A truth-machine (credits goes to this guy for coming up with it) is a very simple program designed to demonstrate the I/O and control flow of a language. Here's what a truth-machine does: Gets a ...
152
votes
279answers
43k views

1, 2, Fizz, 4, Buzz

Introduction In our recent effort to collect catalogues of shortest solutions for standard programming exercises, here is PPCG's first ever vanilla FizzBuzz challenge. If you wish to see other ...
67
votes
212answers
21k views

Is this even or odd?

Note: There is not been a vanilla parity test challenge yet (There is a C/C++ one but that disallows the ability to use languages other than C/C++, and other non-vanilla ones are mostly closed too), ...
64
votes
83answers
12k views

Golf all the 16 logic gates with 2 inputs and 1 output!

For example, the gate A and B is a logic gate with 2 inputs and 1 output. There are exactly 16 of them, because: each logic gate takes two inputs, which can be ...
56
votes
103answers
12k views

List of primes under a million

This is my first code golf question, and a very simple one at that, so I apologise in advance if I may have broken any community guidelines. The task is to print out, in ascending order, all of the ...
87
votes
38answers
21k views

Tips for golfing in Java

Are there any useful shortcuts that can be used in Java? As shown below, import already adds at least 17 characters to a program. ...
38
votes
101answers
5k views

Divisibility test

Task Given two strictly positive integers n and d as input, determine whether n is evenly divisible by d, i.e., if there exists an integer q such that n = qd. You ...
135
votes
28answers
11k views

Making Future Posts Runnable Online with Stack Snippets

Stack Snippets were recently added to PPCG! Reminiscent of JSFiddle, Stack Snippets allow HTML, CSS, and JavaScript to be run directly in posts! Here is a very simple Stack Snippet: ...

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