Questions tagged [binary]
For challenges about binary, or the base 2 number system.
232
questions
26
votes
26
answers
2k
views
Digital Hardness of Integers
To find the digital hardness of an integer, take its binary representation, and count the number of times both a leading and trailing 1 can be removed until it ...
- 14.6k
37
votes
49
answers
10k
views
What is the reverse (binary) bit number?
So you are given a POSITIVE base 10 (decimal) number. Your job is to reverse the binary digits and return that base 10 number.
Examples:
...
- 955
47
votes
28
answers
4k
views
A bit, a nibble or byte?
Inspired by this challenge
Given an integer in the range 0 <= n < 2**64, output the minimum sized container it can fit in out of
bit: 1
nibble: 4
byte: 8
...
- 28.5k
55
votes
73
answers
8k
views
In how many bits do I fit
For any positive 32-bit integer (1 ≤ n ≤ 0xFFFFFFFF) output the number of bits needed to represent that integer.
Test cases
...
- 5,909
16
votes
1
answer
758
views
Every prime bit must alternate
A program is bit primed if bits in prime positions must alternate between zero and one, starting with one.
For example, this is a template for a bit primed program with [0..47] bits.
...
- 1,446
16
votes
9
answers
761
views
Sloping Binary Numbers
Given an integer n, output the first n sloping binary numbers, either 0- or 1-indexed. They are called this because of how they ...
- 23.3k
21
votes
28
answers
2k
views
The Baum-Sweet Sequence
The Baum-Sweet Sequence (A086747 with a Twist)
Take in a positive integer n and print the integers from 1 to n for which the Baum-Sweet sequence returns true. The ...
- 20.6k
45
votes
84
answers
9k
views
Binary to decimal converter
Binary to decimal converter
As far as I can see, we don't have a simple binary to decimal conversion challenge.
Write a program or function that takes a positive binary integer and outputs its ...
- 46.2k
35
votes
25
answers
3k
views
Complex Binary Numbers
Let's create a simple, surjective mapping from positive integers to Gaussian integers, which are complex numbers where the real and imaginary parts are integers.
Given a positive integer, for example ...
- 89.3k
27
votes
21
answers
1k
views
Primenary Strings
A Primenary (binary-prime) string is one which, when written as a binary grid, every row and column has a prime total.
That's quite a vague explanation, so let's break it down with a worked example......
- 14.6k
16
votes
5
answers
2k
views
Binary Convolution
A binary convolution is described by a number M, and is applied to a number N. For each bit in the binary representation of <...
user45941
19
votes
29
answers
2k
views
Binary Countdown Length
inspired by Count down from infinity
Given a non-negative integer N, output the number of repetitions of the following steps it takes to reach 0:
Convert ...
user45941
9
votes
11
answers
880
views
Ordered list of binary sequences of multiple dimensions
Given a positive integer n, output the 2^n binary sequences of length n sorted in the ...
- 117
1
vote
2
answers
285
views
Chained Binary Operations
Chained Binary Operations
Here's a challenge involving truth tables and binary operations. For this specific challenge, your task is to use the following table of operations:
To create a function ...
- 20.6k
101
votes
23
answers
17k
views
Where's the 0xBEEF?
This challenge was inspired by this Wendy's commercial from 1984.
Illustration by T S Rogers
Your task is to find a hexadecimal 0xBEEF on a binary bun.
The 'beef' consists of the following pattern:
...
- 189k
10
votes
9
answers
948
views
Super Folding Numbers
We have already defined a folding number here.
But now we are going to define a Super Folding Number. A Super Folding number is a number that if folded enough times it will eventually reach one less ...
- 96.5k
37
votes
27
answers
3k
views
Folding Numbers
Given a number determine if it is a folding number.
A folding number is a number such that if you take it binary representation and "fold" it in half, That is take the result of XNOR ...
- 96.5k
41
votes
14
answers
5k
views
Incrementing Gray Codes
Introduction
A Gray Code is an alternative to binary representation in which a number is incremented by toggling only one bit, rather than a variable amount of bits. Here are some gray codes along ...
- 2,727
59
votes
27
answers
14k
views
i love yOu i lOve you i love yOu!
XKCD #99, with the title "Binary Heart" shows a simple image of ones and zeros, with some digits colored red.
The red heart is visible to the naked eye, but the message hidden in the binary sequence ...
- 46.2k
9
votes
20
answers
1k
views
String and ASCII [duplicate]
The Challenge
Given a non-empty string containing only lowercase or uppercase letters and no spaces:
Sum up the ASCII values for each character instance in the input string.
The sum will be ...
- 623
33
votes
6
answers
3k
views
Telegraphy Golf: Decode Baudot Code
Background
In 1870 Émile Baudot invented Baudot Code, a fixed-length character
encoding for telegraphy. He designed the code to be entered from a
manual keyboard with just five keys; two operated with ...
- 9,726
12
votes
19
answers
1k
views
All Binary Combinations to Decimal
Disclaimer
This question is not a duplicate of this question. I'm not counting specific digits, as we already have those set in the initial parameters. This question is focusing on the decimal ...
- 7,493
10
votes
11
answers
2k
views
Given an integer, compute its Levenshtein code
Disclaimer: Levenshtein coding is completely unrelated to the Levenshtein edit distance metric.
<Insert long story about why Levenshtein codes need to be calculated here.>
The code
Levenshtein ...
- 17.9k
66
votes
11
answers
4k
views
Only Even Bytes
The scenario
Lately you have been noticing some strange behavior with your favorite text editor. At first it seemed that it was ignoring random characters in your code when writing to disk. After a ...
- 96.5k
17
votes
2
answers
390
views
Given a truth table, output a Stackylogic program that satisfies it
Stackylogic is a programming language I made up in a previous challenge: Run Stackylogic. Read that post for full details and examples, but here is how it works paraphrased:
Stackylogic takes ...
- 89.3k
46
votes
11
answers
2k
views
Run Stackylogic
Stackylogic is a logic-based programming language I made up that take in 0's and 1's for input and outputs a single ...
- 89.3k
29
votes
30
answers
4k
views
Bit-Reversal Permutations
Your goal is to create a function or a program to reverse the bits in a range of integers given an integer \$n\$. In other words, you want to find the bit-reversal permutation of a range of \$2^n\$ ...
- 16.9k
25
votes
23
answers
2k
views
Swap bits with their neighbours
Task description
Given an integer, swap its (2k–1)-th and 2k-th least significant bits for all integers k > 0. This is sequence A057300 in the OEIS.
(The number is assumed to have “...
- 68.1k
15
votes
11
answers
1k
views
What's the Binary Time?
What's the Binary Time?
Everybody knows what the normal time is. It's up there in the top-right (or wherever you put it) of your screen. But a question people rarely seem to ask themselves is this: ...
user53406
31
votes
44
answers
3k
views
Mean bits: an average challenge
Given an integer N >= 1, output the mean number of bits in an integer from 0 to N - 1
Specification
The output can be calculated as the sum of the number of bits in the binary representation of each ...
32
votes
32
answers
2k
views
Decompose binary into alternating subsequences
This was inspired by Problem 13 - Non-Repeating Binary of HP CodeWars' recent competition.
Let's take a random decimal number, say
727429805944311
and look at ...
- 16k
16
votes
11
answers
1k
views
Sum of Binary Substrings
This challenge is simple, given a decimal number, convert to binary, and calculate the sum of the sub-strings of the binary number, whose length is shorter than the original number. Here is an example:...
- 7,502
19
votes
12
answers
4k
views
When will I have a binary car?
I noticed that my car's odometer was at 101101 when I got to work today. Which is a cool number because it's binary (and a palindrome, but that's not important). Now, I want to know when the next time ...
- 3,676
6
votes
1
answer
296
views
Model a probability table using 15-bit fixed probabilities
A histogram is an array of integers that counts the number of times a symbol occurs. For example, for the string "aaabbbabbdebabbbebebdbaaabbabaaaaeebeaabaaba" a ...
- 39k
8
votes
4
answers
513
views
Shortest binary number in range
Given two arbitrarily precise decimal numbers 0 ≤ x < y ≤ 1, compute the shortest (in digits) binary number b such that x ≤ b < y.
Output the binary digits of b after the binary ...
- 39k
12
votes
18
answers
1k
views
Preparing a multiple choice test
Introduction
Note: this is not some kind of method to encourage cheating. As Cᴏɴᴏʀ O'Bʀɪᴇɴ already said, studying is the best solution for passing a test :3.
Consider the following answers to the ...
- 44.3k
29
votes
6
answers
4k
views
1+1 = 10, 1+2 = 3
Write a function or program than can do simple arithmetic (addition, subtraction, multiplication and division) in both base 10 and base 2.
The function will take a mathematical expression as input, ...
- 46.2k
10
votes
3
answers
443
views
I-Ching pair binary computer
Introduction
I Ching is an ancient divination text and the oldest of the Chinese classics. It uses a type of divination called cleromancy, which produces apparently random numbers.
The basic unit of ...
3
votes
5
answers
939
views
Binary Run-Length Encoding [duplicate]
Overview
Run-length encoding — sequences in which the same data value occurs in many consecutive data elements are stored as a single data value and count
When using run-length encoding:
...
- 6,660
23
votes
25
answers
2k
views
Compute the Binary Sierpinski Triangle Sequence
The Binary Sierpinski Triangle sequence is the sequence of numbers whose binary representations give the rows of the Binary Sierpinski Triangle, which is given by starting with a 1 in an infinite row ...
- 4,087
26
votes
36
answers
4k
views
Write out the Thue-Morse sequence
There's quite a few challenges on this site that ask you to print out a sequence, and this is no exception.
(The following explanation of the sequence for this challenge assumes the symbols in the ...
- 12.2k
32
votes
40
answers
3k
views
Parenthifiable Binary Numbers
If you express some positive integer in binary with no leading zeros and replace every 1 with a ( and every ...
- 89.3k
20
votes
17
answers
2k
views
Simplify binary
Challenge
Given a binary number as input through any means, "simplify" the number using a full program or a function.
Input
[binary]
...
- 1,586
24
votes
19
answers
1k
views
Counting +1 primes
Define that the natural number p is a +1 prime of the natural number n if p is a prime number and the standard binary representation (i.e., without leading zeroes) of p can be obtained by adding (i.e.,...
- 210k
27
votes
31
answers
3k
views
Reverse and Invert a String
Reverse and Invert a String
Challenge
In this challenge. You'll be writing a program which will output or return the input, reversed and inverted.
First, each character should be converted to its ...
- 28.9k
6
votes
3
answers
626
views
Symmetric boolean functions as Zhegalkin polynomials
Let \$\mathbb{B} = \mathbb{Z}_2 = \{0, 1\}\$ be the set of booleans. A symmetric boolean function in \$n\$ arguments is a function \$f_S : \mathbb{B}^n \to \mathbb{B}\$ that checks if the number of ...
- 10.1k
32
votes
23
answers
4k
views
Biplex: an important useless operator
Input
A list of between 1 and 255 positive integers (inclusive), each in the range 1 to 232 - 1 (inclusive).
Your input format does not need to be identical to the test cases.
Input without leading ...
31
votes
33
answers
4k
views
Numbers with multiple runs of ones
Task
Find the set of numbers such that the binary representation contains two or more runs of 1 separated by at least one 0.
...
user12166
19
votes
2
answers
942
views
Koopa Shell Sequence
In various Super Mario games green and red Koopa Troopa shells can slide frictionlessly on flat surfaces and destroy brick blocks that are in their way. When a shell hits a brick block the block ...
- 89.3k
10
votes
4
answers
212
views
Counting cycles in a folding and squashing process
In chaos theory, the horseshoe map is an example of how chaos arises in a simple process of folding and squashing. It goes like this: take an imaginary piece of dough, fold it, and finally squash it ...
- 2,891