Questions tagged [source-layout]

For challenges that involve the physical layout or physical manipulation of source-code.

Filter by
Sorted by
Tagged with
160
votes
5answers
15k views

Hyperprogramming: N+N, N×N, N^N all in one

Write a program that takes in a number N from 1 to 9 inclusive. In its native form your program should output N+N. E.g. output 2 if N is ...
139
votes
141answers
19k views

I double the source, you double the output!

Your task, if you wish to accept it, is to write a program that outputs a positive integer (higher than 0). The tricky part is that if I duplicate your source code, the output must be double the ...
132
votes
76answers
20k views

Hello, World! (Every other character)

Write a program that prints "Hello, World!". But also, if you take only the first, third, fifth, etc. characters of your program, the resulting program should still print "Hello, World!". If your ...
119
votes
43answers
17k views

Write a program that always outputs “2012” - even if it's modified!

This idea is not mine, though I don't know where it originated. I once met it in a programming contest very long ago (1998, if I remember correctly). The task is to write a program in your favorite ...
105
votes
35answers
12k views

What are the five most powerful characters in your language?

Choose any five characters your language supports. There are 5! = 5×4×3×2×1 = 120 ways these can be arranged into a 5-character string that contains each character once; 120 permutations. Choose your ...
101
votes
25answers
15k views

Print a Negative of your Code

Consider a square of printable ASCII characters (code points 0x20 to 0x7E) for side length N, like the following (here, N = 6): ...
80
votes
60answers
6k views

From Programming Puzzles to Code Golf

Your task is to write a program that outputs the exact string Programming Puzzles (trailing newline optional), but when all spaces, tabs, and newlines are removed ...
74
votes
11answers
5k views

Error 404: Character Not Found

Scenario One of your friends is struggling on a homework assignment. He needs a simple program which prints the first 404 natural numbers: ...
71
votes
11answers
6k views

Fault-Tolerant Hello World

At the end of your interview, the Evil Interviewer tells you, "We make all of our applicants take a short coding test, to see if they really know what they are talking about. Don't worry; it's ...
66
votes
5answers
5k views

Powerprogramming: O(1^N), O(N^1), O(2^N), O(N^2) all in one

Write a program (or function) that exhibits four common big O time complexities depending on how it is run. In any form it takes in a positive integer N which you may assume is less than 231. When ...
64
votes
29answers
7k views

Write a Rectangular Program that Outputs the Number of Times it was Rotated

The title says it all. Your goal is to write a program that forms a w×h rectangle of characters that can be rotated and re-run to output the number of 90° Counter-Clockwise (CCW) rotations that have ...
55
votes
24answers
6k views

Significant Whitespace

We define whitespace to be any of the three characters, tab (0x09), newline (0x0A) or space (0x20). For this challenge, you're to write two programs or functions in the same programming language, ...
50
votes
50answers
5k views

Third time the charm

Your task, if you wish to accept it, is to write a program that outputs a positive integer (higher than 0). If the source code is duplicated the output must remain the same. The tricky part is that if ...
47
votes
60answers
10k views

I reverse the source code, you negate the output!

Your task, if you wish to accept it, is to write a program that outputs a non-zero number(can be integer or float). The tricky part is that if I reverse your source code, the output must be the ...
47
votes
14answers
7k views

Make a code square with your favorite word

Pick your favorite 6 letter common English word that has no repeated letters, such as wombat. Write a program in an N×N grid of characters without comments such ...
47
votes
16answers
5k views

Sierpinskified Code

Write a rectangular block of text that when arranged into a Sierpinski carpet, using same-sized blocks of spaces for the empty portions, creates a program that outputs the iteration number of the ...
47
votes
3answers
4k views

Coding Around The Clock

Write a single line program two or more characters long that contains no line terminators and takes no input. For example, your program might be: MyProgram When ...
45
votes
23answers
4k views

A Chiral Puzzle

A shape is chiral if no amount of rotation can make it look like it's mirror image. In this puzzle we will be writing chiral computer programs. For this puzzle we will think of a program as a ...
44
votes
19answers
5k views

Create a square of increasing size by replicating the initial code

Your assignment is to write a program of even length, that prints an ASCII-art square (described below), that increases its side length by 1 unit each time the original source code is pasted in the ...
43
votes
3answers
4k views

Code that runs the Game of Life on itself

Write two rectangular blocks of code, each w characters wide and h characters tall, that implement Conway's Game of Life when arranged in a grid. (w and h may be any positive integers) For example, ...
41
votes
53answers
8k views

I reverse the source code, you negate the input!

Blatant rip-off of a rip-off. Go upvote those! Your task, if you wish to accept it, is to write a program/function that outputs/returns its integer input/argument. The tricky part is that if I ...
41
votes
19answers
3k views

Program template for printing *any* string

Write a program with the following properties: When run as-is, the program produces no output (i.e. 0 bytes of output). There is a location within the program (of your choice: it could be at the ...
41
votes
9answers
5k views

Shifting-Oriented Programming

A string can be shifted by a number n by getting the byte value c of each character in the string, calculating ...
40
votes
8answers
6k views

40 Numbers in 9 Bytes

There are 40 ways a directed Hamiltonian path can be arranged on a 3×3 grid: This graphic (thanks Sp3000!) shows only the 20 undirected paths. Traverse each colored line in both directions for the 40 ...
40
votes
12answers
2k views

A well linked challenge

An activity I sometimes do when I'm bored is to write a couple of characters in matching pairs. I then draw lines (over the tops never below) to connect these characters. For example I might write \$...
38
votes
22answers
4k views

Hide the Needle in the Haystack (Cops)

This is part of a cops-and-robbers challenge. Go here for the robbers' part. The Cops' Challenge You should write a program or function in a language of your choice, which outputs the string ...
38
votes
18answers
3k views

Prime Up your code

Input no input for this challenge The Challenge Write a code that outputs: The first 10 prime numbers whose sum of their digits equal the number of bytes of your code Examples Let's say your code is <...
37
votes
28answers
4k views

Is the matrix centrosymmetric… and so is the code?

Defintion A centrosymmetric matrix is a square matrix that is symmetric about its center. More rigorously, a matrix \$A\$ of size \$n \times n\$ is centrosymmetric if, for any \$i,\: j \in ([1, n] \...
36
votes
24answers
5k views

Double-time is not double time

Based on this challenge. In the rhythm game osu!, the difficulty modifier "Double-time" actually only increases the speed by 50%. Your task, is to write a program that outputs a positive ...
36
votes
24answers
6k views

I transpose the source code, you transpose the input!

Rip-off of a rip-off of a rip-off of a rip-off. Go upvote those! Your task, if you wish to accept it, is to write a program/function that outputs/returns its input/argument¹. The tricky part is that ...
36
votes
5answers
1k views

Letter, Number, Symbol, Space, Repeat

There are 97 ASCII characters that people encounter on a regular basis. They fall into four categories: Letters (52 total) ...
35
votes
17answers
3k views

Hidden Inversions (Cops' Thread)

This is a cops-and-robbers puzzle the robbers' thread can be found here. Your task will be two write two programs (or functions) such that they are anagrams of each other and one performs the left ...
34
votes
18answers
4k views

Jumblers vs Rebuilders: Coding with Tetris Bricks

In traditional Tetris, there are 7 distinct tetromino bricks, each denoted by a letter similar to its shape. ...
34
votes
3answers
2k views

Programming Tetris Blocks (Literally)

In the game Tetris, there are 7 types of bricks or Tetriminoes, which are mathematically known as tetrominoes because they are all made with 4 square segments: The have the names I, J, L, O, S, T, ...
33
votes
29answers
5k views

Double it your way

There have been a couple of challenges involving doubling source code: here and here. The task we have here is a bit harder, but should be doable in almost every language. In this challenge, you will ...
33
votes
11answers
2k views

Multiplication by Self-Modification

...at least for some definition of "self-modification". The Task In this challenge, your task is to write three strings A, B ...
33
votes
5answers
2k views

Make The Finest Magic Code Square

In math a magic square is an N×N grid of numbers from 1 to N2 such that every row, column, and diagonal sums to the same total. For example here's a 3×3 magic square: In this challenge we'...
32
votes
19answers
2k views

Inverse function

Wouldn't it be neat if programming functions could be inverted, just like the mathematical function they implement? Write a function (or program) that takes one input ...
32
votes
20answers
2k views

Figure and Ground

Source: Wikipedia For this challenge, you should write two programs which resemble the figure and ground of the above image, such that one of them prints figure ...
32
votes
23answers
4k views

Cat, Quine, Hello World

Write a cat program, a quine, and a Hello World in the same language such that when two specific programs of the three are concatenated in a certain order, you get the third program. It does not ...
32
votes
8answers
4k views

One hundred passwords

I have one hundred vaults, each one within another. Each vault has a password, consisting of a single number. 95 43 81 89 56 89 57 67 7 45 34 34 78 88 14 40 81 23 26 78 46 8 ...
31
votes
7answers
5k views

What did we forget?

Your task is to write a non-empty computer program comprised of some sequence of bytes. If we choose a particular byte in the program and remove all instances of it from the program, the modified ...
31
votes
6answers
3k views

Write A Program That Outputs Its Mirror Level

There are 95 printable ASCII characters: !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~ In the ...
31
votes
14answers
4k views

2 Cats in a Quine

Challenge Make two programs, A and B, which are both cat programs in the same language. When concatenated, AB (also in the same language) should be a quine. For example, suppose ...
31
votes
9answers
7k views

Build a twisted “Hello world!”

Your job is quite simple, write a program that prints Hello, world!, that when twisted creates a program that prints Twister!. ...
30
votes
38answers
4k views

I uppercase the source code, you reverse the input!

It's one of these again :D Your task, if you wish to accept it, is to write a program/function (without any uppercase letters) that outputs/returns its string input/argument. The tricky part is that ...
30
votes
54answers
6k views

Internal Truth Machine

It's a normal truth machine but instead of taking input, it uses the first character of the program. Thus, internal. The 0 and 1 are plain characters, i.e. ASCII code 0x30 and 0x31 respectively. ...
30
votes
24answers
2k views

Join N copies of a snippet to produce N^2 characters

Challenge Write the shortest snippet of code possible such that, when N copies of it are concatenated together, the number of characters output is N2. N will be a positive integer. For example if the ...
30
votes
8answers
3k views

Beatles Songs and Hexagons

Write two triangle (i.e. pyramid) shaped programs. The first one should be an upwards pointing text triangle with a minimum base width of three characters. So it would have a structure like ...
30
votes
28answers
2k views

Concatenative counting

Your challenge is to write N snippets of code such that, when you concatenate the first K ≥ 1 together, they produce the number K. The higher N, the better. Here's the catch: you may not use any ...