Questions tagged [number]
A competition to solve a particular problem through the usage and manipulation of numbers.
1,221
questions
25
votes
17
answers
965
views
Cartesian LCM of two arrays
Given two nonempty arrays of natural numbers \$a\$ and \$b\$, return the shortest nonempty array of pairs of natural numbers \$q\$ such that the sequence of first elements of \$q\$ consists of a whole ...
16
votes
6
answers
3k
views
What's the Mayan date?
Just over seven years ago, everybody suddenly stopped talking about the Maya people. It is time to rectify that!
For clarification, I am talking about the Mesoamerican Long Count Calendar. Your ...
15
votes
9
answers
444
views
Partitioning Digits into Distinct Integers
Given a sequence of base-10 digits, output the longest list of integers that contains all the digits exactly once, in the order in which they appeared in the input, without repeating any integers.
...
0
votes
1
answer
215
views
Determine if a number is less than another [closed]
Introduction
Your job is to write a function or program that detects if a number a is less than a number b.
But... You are not ...
12
votes
1
answer
309
views
Maximal 2-distance Sets
In the plane (\$\mathbb R^2\$) we can have at most five distinct points such that the distances from each point to every other point (except itself) can assume at most two distinct values.
An example ...
17
votes
1
answer
663
views
Is this ordinal prime?
You are given an countable ordinal \$1 < r < \varepsilon_0\$. Determine whether or not it is prime. If not, provide exactly two ordinals \$r_0, r_1 < r\$ such that \$r_0r_1 = r\$, following ...
24
votes
41
answers
5k
views
Round up my number
Sandbox
Given two positive integers a and b, return the smallest multiple of b that is greater than or equal to a.
Examples
Definitions: true = ...
17
votes
23
answers
3k
views
Size Does Matter (at least referring to bottles)
Introduction
I have an even number of bottles, all of different sizes. Unfortunately, I only know the size of the smallest bottle: 300ml.
I also know the following:
Half of the bottles are twice ...
-5
votes
2
answers
379
views
Fastest N times Hello World (Java/C/ C++) [closed]
Not a new one:
Input
N, being n, 0 ≤ n ≤ 5.
Output
N times "Hello World."
Example:
Input
3
Output
Hello World.
Hello World.
Hello World.
These 2 are my ...
10
votes
23
answers
2k
views
Max of the reversed of two numbers
Given two real numbers (postive or negative) in the limits of float pointing number data types, i.e., (\$-3.4e38\$ to \$3.4e38\$) not inclusive, you should output the max of the two reversed numbers.
...
16
votes
6
answers
756
views
Roman Numeral Counting
Roman numerals can be (mostly) written in a one column format, because each letter intersects the top and the bottom of the line. For example: I, or 1 intersects ...
15
votes
11
answers
2k
views
Reach the number in minimum steps
In this challenge, you are given a number x. You have to find the minimum number of steps required to reach x from 1. At a particular point, you have two choices:
1) Increment the number by 1.
2) ...
37
votes
10
answers
3k
views
Interpret numbers very literally
To interpret a positive integer very literally, write it in English words (without "and"), replace hyphens with spaces, replace each resulting word with its number value, and concatenate the ...
14
votes
8
answers
538
views
Output integer given a digital clock style input
Input
_ _ _ _ _ _ _ _
| _| _||_||_ |_ ||_||_|| |
||_ _| | _||_| ||_| _||_|
output
1234567890
Rules
...
15
votes
4
answers
509
views
List where pinballs would exit a grid of bumpers from different entrance points
Inspired by this lumosity mini game, Pinball Recall
We start with a rectangular grid (viewed from above) with several bumpers as follows. Entrances/exits are numbered counter-clockwise starting from ...
25
votes
14
answers
3k
views
Are my triangles similar?
Given (in any structure; flat list, two lists of lists, a tuple of matrices, a 3D array, complex numbers,…) the coordinates for two non-degenerate triangles ...
16
votes
10
answers
1k
views
Digit Date Range
NOTE: Since I'm Dutch myself, all dates are in the Dutch dd-MM-yyyy format in the challenge description and test cases.
Challenge:
Inputs:
Start date \$s\$; End ...
5
votes
7
answers
257
views
Replace by most recent nonzero [duplicate]
Given a non-empty list of decimal digits (0, 1, ..., 9), replace each zero by the most ...
44
votes
30
answers
9k
views
French license plates
Sandbox
French License Plates
French license plates come in a sequential order, following a specific pattern of numbers and letters : AB-012-CD
Challenge
Write ...
29
votes
20
answers
3k
views
Calculate the Ultraradical
What is the Ultraradical?
The ultraradical, or the Bring radical, of a real number \$a\$ is defined as the only real root of the quintic equation \$x^5+x+a=0\$.
Here we use \$\text{UR}(\cdot)\$ to ...
26
votes
36
answers
4k
views
Convert a string of digits from words to an integer
Convert a string containing digits as words into an integer, ignoring leading zeros.
Examples
"four two" -> 42.
...
3
votes
9
answers
247
views
Given a sequence of numbers, print out all possible sets such that the sum is less than a number
The problem has 3 inputs.
L: a list of all numbers
size: the size each set can be
max: the max sum amongst each set
The challenge is as follows:
Given L, size and max, construct as many sets from ...
25
votes
20
answers
8k
views
1, 2, 4, 8, 16, ... 33?
Challenge
Write a function/program that outputs either the n'th element, or the first n elements, in the well known number ...
41
votes
61
answers
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 ...
17
votes
7
answers
1k
views
Decimal “XOR” operator
Many programming language provide operators for manipulating the binary (base-2) digits of integers. Here is one way to generalize these operators to other bases:
Let x and y be single-digit numbers ...
14
votes
11
answers
839
views
Output Distinct Factor Cuboids
Output Distinct Factor Cuboids
Today's task is very simple: given a positive integer, output a representative of each cuboid formable by its factors.
Explanations
A cuboid's volume is the product ...
20
votes
18
answers
2k
views
What's this constructed number's starter?
A number of programming languages construct large integers through 'concatenating' the digit to the end of the existing number. For example, Labyrinth, or Adapt. By concatenating the digit to the end, ...
34
votes
39
answers
6k
views
Round away from zero
Round away from zero
Inspired by Round towards zero.
Given a number input via any reasonable method, round the number "away from zero" - positive numbers round up, and negative numbers round down.
...
44
votes
17
answers
6k
views
First Number to Contain Each Letter
Given a single letter from A to Z (except J and K) as input, output the smallest non-negative integer containing that letter in its written form. Assume numbers never contain the word "and", so ...
30
votes
21
answers
6k
views
Divide Numbers by 0
We've all been told at some point in our lives that dividing by 0 is impossible. And for the most part, that statement is true. But what if there was a way to perform the forbidden operation? Welcome ...
20
votes
68
answers
6k
views
Round towards zero
This is a simple task. Given a positive or negative real number, round it to the next whole integer closer to zero.
The challenge
Take input through any reasonable form (stdin, function, etc.) of ...
22
votes
9
answers
2k
views
Levenshtein Neighbours
Most square numbers have at least 1 different square number with which their Levenshtein distance is exactly 1. For a given square \$x\$, each square that meets this condition is called a Levenshtein ...
18
votes
19
answers
2k
views
Simplification of numbers
How, you can’t remember the 6 or 7-digit phone number that appeared on the TV screen for a second?! Using the special technique described below, you will turn into a walking phonebook!
Obviously, the ...
10
votes
6
answers
5k
views
Determine Beckett Grading Service (BGS) Final Grade
Introduction:
Beckett Grading Service (aka BGS), is a company which encapusulates and grades Trading Card Game (TCG) cards (i.e. sport cards, Magic The Gathering, Pokémon, Yu-Gi-Oh, etc. etc.). The ...
11
votes
17
answers
2k
views
Alphanumeric Line and Curve Counting
Given an input string, write a program that outputs the total number of lines and curves it has.
The Challenge
Take input from STDIN, or any other input method.
...
29
votes
55
answers
6k
views
Integer Lists of Noah
Introduction:
I think we've all heard of it, but here a very brief summary: Noah gathered two of every species of animal on the planet, male and female, to save in his Ark during a great flood. The ...
10
votes
17
answers
1k
views
Tesco's Burger Relish Best Before End date number
Given a date between 2010-01-01 and 2099-12-31 as three integers (please state your order if not [year,month,day]), answer with Tesco's corresponding five-digit ...
-6
votes
4
answers
268
views
Is this number a palindrome? [closed]
Input
A single integer in your language's preferred format, e.g int or an array of digits are all acceptable.
Output
A truthy or falsely value, depending on ...
39
votes
31
answers
15k
views
Do the 26 richest billionaires own as much wealth as the poorest 3.8 billion people?
Introduction:
A few days ago I read this post with the same title when I came across it in the HNQ. In this question it is being discussed if the claim of president-candidate Bernie Sanders, who ...
13
votes
3
answers
518
views
Implement a strongly Darboux function
According to Wikipedia, a strongly Darboux function is
one for which the image of every (non-empty) open interval is the whole real line
In other words, a function \$f\$ is strongly Darboux if ...
26
votes
19
answers
3k
views
Analog is Obtuse!
An analog clock has 2 hands*: Hour and minute.
These hands circle the clock's face as time goes by. Each full rotation of the minute hand results in 1/12th of a rotation of the hour hand. 2 full ...
9
votes
0
answers
246
views
Fastest way to iterate over sublattice of discrete lattice
I need to construct a functor that iterates over the linear representation of a sub-lattice of size \$d_x,d_y,d_z,d_q\$ embedded in a lattice of size \$n_x,n_y,n_z,n_q\$. The sub-lattice corner is ...
14
votes
4
answers
478
views
Distributing parliament seats
Introduction
In a general election, one would like to calculate a constant price per parliament seat. This means that for N >= 0 seats to be distributed and a ...
22
votes
6
answers
1k
views
Subtract the Folded Matrix
Challenge:
Given an NxN matrix where \$N\geq2\$ and one of eight distinct 'folding options', output a 2D array/list with the subtracted values.
The eight folding options are: left-to-right; right-to-...
13
votes
7
answers
502
views
Print the total length of all "quoted" characters
Rules
In this challenge, I'm going to redefine the definition of "quotes" a bit.
Quotation marks (AKA quotes) are any identical characters used in pairs in various writing systems to set off direct ...
12
votes
6
answers
989
views
Group Integers by Originality
Introduction:
I collect twisty puzzles. Most twisty puzzles are produced and sold by Chinese companies. Most well-known companies ask permission from puzzle designers to produce their designs and work ...
17
votes
35
answers
2k
views
Incremental Ranges!
Your task is to, given two positive integers, \$x\$ and \$n\$, return the first \$x\$ numbers in the incremental ranges sequence.
The incremental range sequence first generates a range from one to \$...
21
votes
23
answers
3k
views
Rotated Position of Integers
Challenge:
Input:
A sorted list of positive integers.
Output:
The amount of integers which are still at the exact same index, after rotating the digits in each integer its index amount of times ...
9
votes
4
answers
641
views
Leading and Suffering Numbers
Introduction:
In Dutch, the words leading and suffering, being 'leiden' and 'lijden' respectively, are pronounced the same way. One is written with a "short ei", and one with a "long ij&...
36
votes
18
answers
3k
views
Count rotary dial pulses in a phone number (including letters)
In your grandparents' day, dialing a phone number was done with a rotary dial like this:
To dial each digit, put your finger in the corresponding hole, pull it over to the finger stop, and release it....