Linked Questions
78 questions linked to/from Is this number a prime?
14
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28
answers
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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 ...
- 42.3k
9
votes
20
answers
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 ...
- 169
6
votes
15
answers
991
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, ...
- 42.3k
-1
votes
6
answers
364
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 ...
- 7,349
-3
votes
5
answers
208
views
Prime decimal representations of prime binary numbers [duplicate]
Problem Statement: Consider a number n in base-10. Find the smallest base-10 integer i greater than ...
- 233
515
votes
969
answers
188k
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 ...
- 196k
242
votes
450
answers
63k
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 ...
- 2,697
144
votes
566
answers
46k
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 ...
- 13.1k
172
votes
489
answers
35k
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 ...
- 11.2k
194
votes
413
answers
74k
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 ...
- 23.3k
78
votes
261
answers
25k
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), ...
- 5,353
79
votes
94
answers
17k
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 ...
- 49.6k
65
votes
113
answers
17k
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 ...
- 801
106
votes
39
answers
27k
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.
...
- 1,477
43
votes
112
answers
6k
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 ...
- 49.6k