Questions tagged [number]
This challenge is intended to be solved by using, manipulating, accepting as input, or outputting numeric values.
1,087
questions
18
votes
22answers
2k views
3
votes
5answers
73 views
Find the binary period [duplicate]
We know that not all fractions have a terminating binary representation. However every fraction can be written as a leading portion followed by a repeating portion. For example \$1/3\$ starts with \$...
25
votes
9answers
751 views
Mad Libs number sequences
My robot for generating Mad Libs-style sequence challenges has gone rogue! To defeat it, I need you to write code that can solve all the challenges it can crank out.
Your input is three selections ...
22
votes
10answers
3k views
Any lips images
Introduction
The \$n\$-ellipse is a generalization of the ellipse with possibly more than two foci. Specifically, given \$n\$ points on the plane, called foci, the \$n\$-ellipse is the set of points ...
20
votes
8answers
966 views
Counting Distinct Real Roots of Low-Degree Polynomials
Challenge: I want to know about the real roots of polynomials. As a pure mathematician, I care about the existence of such roots, rather than their numeric values.
The challenge is to write the ...
22
votes
22answers
2k views
Find self-locating strings in a number
Based on this Numberphile video
A self-locating string is a number (or set of numbers) in a decimal expansion which corresponds to its location, from the start of the decimal.
For example, take the ...
15
votes
5answers
798 views
How many unique one sided polyominos
Context
From Wikipedia:
A polyomino is a plane geometric figure formed by joining one or more equal squares edge to edge.
one-sided polyominoes are distinct when none is a translation or rotation of ...
17
votes
35answers
2k views
Is it a doubling sequence?
A doubling sequence is an array of numbers where each subsequent number is at least twice the previous number.
Given an ordered list of numbers, determine if the numbers in the list (\$n_{x}\$) have ...
9
votes
5answers
185 views
Count switches in a smallest square root sequence mod \$2^n\$
Definition
For any \$a\equiv1\ (\text{mod }8)\$ and \$n\ge3\$, there are exactly 4 roots to the equation \$x^2\equiv a\ (\text{mod }2^n)\$. Now, let \$x_k(a)\$ be the smallest root to the equation \$...
14
votes
15answers
1k views
Find the Inverse Neighbor Pairs
Definition
We say a pair of integers \$(a,b)\$, where \$0<a<b<N\$ and \$N\$ is an integer larger than 4, is an inverse neighbor pair respect to \$N\$ if \$ab\equiv1\text{ }(\text{mod }N)\$ ...
18
votes
13answers
1k views
Number of palindrome splits
In this task you will take as input a non-negative integer \$n\$, and output the number of pairs of non-negative integers \$a,b\$ such that both are palindromes*, \$a \leq b\$, and \$a+b = n\$. For ...
20
votes
24answers
2k views
Power-Ending Patterns
When you look at the last decimal digit of each power of a non-negative integer a repeating pattern forms. For example, 3:
...
34
votes
35answers
6k views
Shift right by half a bit
The challenge is to implement a program or function (subsequently referred to as "program") that takes a nonnegative integer \$n\$ as input and returns \$n\over\sqrt{2}\$ (the input divided by the ...
22
votes
15answers
865 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
6answers
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 ...
14
votes
9answers
418 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
1answer
194 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 ...
11
votes
1answer
255 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 ...
15
votes
1answer
511 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 ...
21
votes
38answers
4k 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
22answers
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
2answers
279 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
23answers
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.
...
15
votes
6answers
463 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
10answers
835 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
10answers
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 results ...
13
votes
8answers
461 views
Output integer given a digital clock style input
Input
_ _ _ _ _ _ _ _
| _| _||_||_ |_ ||_||_|| |
||_ _| | _||_| ||_| _||_|
output
1234567890
Rules
...
15
votes
4answers
480 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
14answers
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
10answers
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
7answers
243 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
30answers
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 ...
25
votes
18answers
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 \$UR(\cdot)\$ to denote ...
20
votes
26answers
3k 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
9answers
235 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
20answers
7k 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 ...
40
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 ...
16
votes
7answers
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
11answers
799 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 ...
16
votes
17answers
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, ...
26
votes
31answers
4k 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.
...
42
votes
17answers
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 ...
19
votes
18answers
5k 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 ...
15
votes
59answers
4k 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 ...
21
votes
9answers
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 ...
asked Aug 17 '19 at 22:44
caird coinheringaahing
13.7k3 gold badges35 silver badges102 bronze badges
17
votes
18answers
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 ...
9
votes
6answers
1k 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 ...
10
votes
17answers
1k 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.
...
-3
votes
4answers
111 views
One square root function for unsigned numbers [closed]
One square root function for unsigned numbers
Write the function sqrti(x) that from one not negative integer number x, it returns the integer square root of that number truncate to the 0 digit, so ...
27
votes
54answers
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 ...
