Questions tagged [number]
This challenge is intended to be solved by using, manipulating, accepting as input, or outputting numeric values.
978 questions
0
votes
2answers
135 views
Work out \$x^y\$ using only addition and subtraction [duplicate]
The challenge is to implement a function or program that takes two numbers, \$x\$ and \$y\$ and return the result of \$x^y\$.
The program cannot use any other mathematical operation other than \$+\$ ...
24
votes
15answers
3k views
Matrix Jigsaw Puzzles
Input:
An integer n
Two equal-sized square matrices (with their width/height being a multiple of n)
Output:
One of two ...
24
votes
38answers
2k views
Enumerate each series of identical numbers in-place
Given a list of strictly positive integers, go through each distinct number and replace all occurrences of it with successive indices (zero or one based) of a new series.
Examples
...
6
votes
11answers
388 views
Mis-decode a date
Background
Inspired by a now deleted question by John Burger from which I quote:
Now obviously no human made this mistake. It's a mis-decode of something - perhaps the ISBN? My question is: ...
5
votes
1answer
265 views
Surreal Numbers
Surreal Numbers
Surreal numbers are one way of describing numbers using sets. In this challenge you will determine the value of a surreal number.
Intro
A surreal number consists of two sets: a left ...
11
votes
7answers
320 views
Approximate the proportion of integers with neighboring factors
If 1 is not counted as a factor, then
40 has two neighboring factors (4 and 5)
1092 has two neighboring factors (13 and 14)
350 does not have two neighboring factors
(out of its factors 2, 5, 7, 10, ...
1
vote
0answers
68 views
Sino-Korean numerals [duplicate]
The Korean language has two sets of numerals, a native Korean numerals and Sino-Korean numerals.
The native Korean numerals are mostly used for numbers under 100, such as age and time.
The Sino-...
27
votes
20answers
2k views
Convert to Suzhou numerals
Suzhou numerals (蘇州碼子; also 花碼) are Chinese decimal numerals:
0 〇
1 〡 一
2 〢 二
3 〣 三
4 〤
5 〥
6 〦
7 〧
8 〨
9 〩
They pretty much work like Arabic numerals, except ...
0
votes
3answers
160 views
Round the digits last digit, over and over
Challenge:
Given two inputs, x and y, round x to one less significant figure, then repeat until it has y number of unrounded digits left. (the decimal point does not count as a digit)
Input & ...
16
votes
7answers
562 views
Satisfying Rounding
Satisfying Rounding
You know when you're in science class, and asked to round to 2 sig figs, but your answer is 5.2501...? You should round to ...
10
votes
1answer
495 views
Golf a number bigger than Loader's number
As a follow up to Shortest terminating program whose output size exceeds Graham's number and Golf a number bigger than TREE(3), I present a new challenge.
Loader's number is a very large number, ...
13
votes
26answers
1k views
Self-contained powers
Given integer n, output the smallest exponent e greater than 1 such that n^e contains ...
31
votes
42answers
4k views
Print all lexicographically increasing numbers under 10000
A lexicographically increasing number is an integer whose digits are in strictly increasing order. Print all lexicographically increasing numbers under 10000.
Here are lines of the expected output:
...
0
votes
2answers
148 views
Number letter counts [closed]
If the numbers 1 to 5 are written out in words: one, two, three, four, five, then there are 3 + 3 + 5 + 4 + 4 = 19 letters used in total.
Output how many letters would be used if all the numbers from ...
7
votes
3answers
843 views
Largest Number in Brainfuck BigInt for each program length up to 50 instructions
This challenge is for the largest finite number you can get BrainFuck programs of given lengths to contain in memory.
We must use one of the BF versions that uses big integers for the cells rather ...
23
votes
25answers
2k views
Sort by Largest Digit(s)
Challenge:
Given a list of integer, sort descending by their single largest digit(s). The order for numbers with the same largest digit are then sorted by second largest digit, etc.
We ignore ...
15
votes
30answers
2k views
Upward and onward to greater glory!
May this challenge serve as (another) tribute to Stan Lee, who passed away aged 95.
Stan Lee has left us an invaluable legacy and a peculiar catch word: Excelsior. So here's a small challenge based ...
10
votes
9answers
1k views
Through Space and Time
Introduction:
In general we usually speak of four dimensions: three space dimensions for x, y, and ...
12
votes
40answers
2k views
Print the Lost numbers
As a big fan of the Lost TV series, I always got intrigued by the sequence of numbers that repetitively appears on the episodes. These numbers are:
\$ 4, 8, 15, 16, 23, 42\$ (A104101)
Using any ...
0
votes
4answers
429 views
Fastest algorithm to output array containing all integers in range excluding duplicate digits
Input is a single integer in ascending digit order.
The only valid inputs are:
12
123
1234
...
7
votes
12answers
821 views
Decimal Digit Truncating
Input:
A decimal
Output:
The input truncated
How to truncate them?
The integer part of the input will remain the same. The decimal part of the input will be truncated based on the lowest digit in ...
6
votes
4answers
156 views
Seeking Substantial Subcollections
(thanks to @JonathanFrech for the title)
Challenge
Write a program or function that, given a collection of positive integers \$S\$ and a positive integer \$n\$, finds as many non-overlapping ...
5
votes
1answer
102 views
Minimum 1's to get 1-expression for n [duplicate]
Background
Challenge is inspired by this question.
The 1-expression is a formula that in which you add and multiply the number 1 any number of times. Parenthesis is allowed, but concatenating 1's (e....
-4
votes
20answers
380 views
Array indexes to number and number reversed
Given an input array having minimum length 2 and maximum length 9 having any initial values output an array having length ...
20
votes
36answers
8k views
IP address or not?
Your network scanning tool is annoyingly picky about input, and immediately crashes if you feed it an IPv4 address that contains improper characters or isn't properly formatted.
An IPv4 address is ...
37
votes
51answers
9k views
List all possible titles for the Anno games
In the Anno video game series there are 6 games with a 7th one announced for early 2019. Their titles always feature a year in a specific pattern:
...
21
votes
23answers
2k views
Minimal Power Root
The minimal power iteration of a number \$n\$ is defined as follows:
$$\text{MPI}(n):=n^{\text{min}(\text{digits}(n))}$$
That is, \$n\$ raised to the lowest digit in \$n\$. For example, \$\text{MPI}(...
33
votes
25answers
5k views
Can the number be split into powers of 2?
Yesterday while playing with my kid I noticed the number in his toy train:
So we have $$4281$$ that can be split into $$4-2-8-1$$ or $$2^2-2^1-2^3-2^0$$
So simple challenge: given a non-negative ...
15
votes
5answers
809 views
The Binary Fences
Input:
An integer n in the range 2 <= n <= 10
A list of positive integers
Output:
Convert the integers to their binary ...
15
votes
9answers
605 views
Stagger, stack, sum
Inspired by this Stack Overflow question.
The challenge
Input
An array of square matrices containing non-negative integers.
Output
A square matrix built from the input matrices as follows.
Let \$...
-3
votes
5answers
76 views
Concatenate 2 numeric type values to a fixed size number [closed]
You have 2 numbers, both stored separate as numeric data type.
First number is always 6 digits long.
Second number can vary between 1 and 4 digits. If it's less than 4 digits, it needs to be padded ...
10
votes
13answers
884 views
Multiply and Divide
Given a value x find the smallest numerical value greater than y that is capable of being multiplied and divided by x while retaining all original digits.
The new numbers do not lose digits.
The new ...
17
votes
18answers
4k views
Longest Repeating Subsequence of a Single Digit
Challenge:
Given a positive integer, output the longest single-digit subsequence that occurs at least twice, AND has boundaries of another digit (or the start/end of the integer).
An example:
Input:...
31
votes
41answers
5k views
Half, Half Half, and, Half
Consider the following number sequence:
\$ 0, \frac{1}{2}, \frac{1}{4}, \frac{3}{4}, \frac{1}{8}, \frac{3}{8}, \frac{5}{8}, \frac{7}{8}, \frac{1}{16}, \frac{3}{16}, \frac{5}{16}, \frac{7}{16}, \...
16
votes
18answers
5k views
Simplistic Lava Lamp
Introduction:
I think everyone knows what a Lava Lamp is, but in case they do not:
(Image source)
They're basically glass tubes that contain wax in a translucent liquid. The bottom part is heated ...
17
votes
39answers
1k views
Sum \$\text{Square}^2\$
Let \$n=42\$ (Input)
Then divisors are : 1, 2, 3, 6, 7, 14, 21, 42
Squaring each divisor : 1, 4, 9, 36, 49, 196, 441, 1764
Taking sum (adding) : 2500
Since \$50\times 50=2500\$ therefore we return ...
23
votes
38answers
2k views
Expand some number
This challenge is based on this Stackoverflow question.
With a positive number as input, output it as the sum of each digit multiplied by its power-of-10 representation.
Input
A number, as an ...
21
votes
15answers
2k views
Crown hundred crownty crown
I noticed a certain game had a peculiar life counter, which instead of stopping at 999, gained a new digit – the next number was crown hundred or ...
7
votes
3answers
316 views
Print a Quinella Table
ALERT: IN CASE YOU DOUBT, NO PUN ON "QUINE" IS INTENDED
In regulated horse-racing for gambling, bets called Quinella bets exist and in which a person bet on the first two places of a race. In ...
13
votes
52answers
2k views
Are all three integers distinct?
You will be given 3 integers as input. The inputs may or may not be
different from each other.
You have to output 1 if all three inputs
are different from each other,
and 0 if any input is ...
14
votes
2answers
364 views
Impatient divisibility test
Your task is to write a program or function
that determines whether a number is divisible by another.
The catch is that it should give an answer as soon as possible,
even if not all digits of the ...
7
votes
17answers
549 views
Extract and Divide
Challenge
For a given positive integer \$n\$:
Repeat the following until \$n < 10\$ (until \$n\$ contains one digit).
Extract the last digit.
If the extracted digit is even (including 0) multiply ...
0
votes
0answers
128 views
Make n n n n = x [duplicate]
Background
So I've been inspired by this puzzleing SE question to create a similar Code Golf challenge. The basic puzzle format is you must use 4 numbers, such as 5 5 5 5, to equal some other number, ...
13
votes
7answers
647 views
Make the biggest and smallest numbers
Inspired by this post over on Puzzling. Spoilers for that puzzle are below.
Given three positive integers as input, (x, y, z), construct the inclusive range ...
11
votes
16answers
2k views
Prime numbers in large number
Given a large number (in base 10), such as 1234567891011121314151617, find prime "subnumbers" in it.
A prime "subnumber" is a consecutive sequence of digits (taken from the input), which represents a ...
26
votes
23answers
2k views
Compare version numbers
When we publish some software, we assign a version number to it. And users may want to update to the latest version of some software. So, it is the time to find out which version should be newer.
...
18
votes
34answers
3k views
Tower of strings
Given a string of text, output it as a 'tower'.
Each slice of the string (of the form 0:n) is repeated 5*n times, so the first ...
17
votes
22answers
2k views
Sort by what the digit pairs describe
Given a positive integer, we can form a new number that's described by its digits taken pairwise (with a leading 0 added for numbers with odd number of digits).
For eg.:
1234 can be read as one 2, ...
9
votes
6answers
457 views
Codegolf Rainbow : Sorting Colors with Reflection
Introduction:
After I posted two rainbow-related challenges: Codegolf Rainbow : Fun with Integer-Arrays 1 and Codegolf Rainbow : Draw in Black-and-White 2, the following comment was made by @ChrisM ...
29
votes
18answers
1k views
Custom Number Base Converter
The powers that be want to be able to quickly convert any number they have into their own number base using any format they would like.
Input
Your program must accept 3 parameters.
Number: The ...
