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Questions tagged [fastest-code]

The winner of a fastest-code challenge is determined by the runtime performance of the submissions. For fairness, all submissions should be benchmarked on the same machine, which usually means all submissions have to be tested by the host of the challenge. For scoring by asymptotic time complexity, ...

5
votes
2answers
3k views

Fastest modular exponentiation

The challenge is to write code in any open source, available on linux, language of your choice to perform modular exponentiation. The input will be two randomly chosen 2048 bit positive integers ...
10
votes
3answers
655 views

Quickly divide in Manufactoria

Background Manufactoria has been marketed as a game, but we code-golfers can see it for what it really is: a two-dimensional programming language. The Manufactoria programming language is based ...
19
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2answers
1k views

The number of possible numeric outcomes of parenthesizations of 2^2^…^2

Consider an expression 2^2^...^2 with n operators ^. Operator ...
6
votes
3answers
1k views

The making of “Spot It!”: Finding almost unique sets

Puzzle: Find a deck of c cards, each containing p pictures, such that no two pictures match on a given card, and exactly 1 picture on each card matches exactly 1 picture on each of the other cards, ...
16
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3answers
12k views

Fastest code to find the next prime

The problem is as follows. Input: An integer n Output: The smallest prime bigger than n. The challenge is to give the ...
1
vote
4answers
535 views

Race to a Million

This falls under the Code puzzles the best. Fastest way to render the numbers 1-million in a web browser. Preferably using PHP, but use what you must. Numbers must be more than one on a line in the ...
16
votes
3answers
3k views

Longest non-repeating Game-of-Life sequence

Given a positive integer N, determine the starting pattern on a N x N-grid that yield the longest non-repeating sequence under Game of Life-rules, and ends with a fixed pattern (cycle of length 1), ...
4
votes
3answers
4k views

Secret Santa Challenge [duplicate]

Possible Duplicate: Holiday Gift Exchange Background: Secret Santa is a Western Christmas tradition in which members of a group or community are randomly assigned a person to whom they ...
24
votes
2answers
12k views

Fastest semiprime factorization

Write a program to factorize a semi-prime number in the shortest amount of time. For testing purposes, use this: 38!+1 (523022617466601111760007224100074291200000001) It is equal to: ...
2
votes
2answers
417 views

given prime factors of a number, what is the fastest way to calculate it's proper divisors? [closed]

Given prime factors of a number, what is the fastest way to calculate divisors? ...
4
votes
2answers
487 views

List ALL prime-factorized natural numbers in ANY order

This is a variant of List prime-factorized natural numbers up to N in ascending order, but the solutions can be very different. Write a program that outputs prime factorizations of all natural ...
8
votes
3answers
1k views

List prime-factorized natural numbers up to N in ascending order

For a given n list prime factorization of all natural numbers between 1 and n in ascending ...
-3
votes
10answers
9k views

Triangle Puzzle [closed]

Triangle Puzzle Consider the triangle below. This triangle would be represented by the following input file.    5   9 6  4 6 8 0 7 1 5 By starting at the top and ...
5
votes
4answers
13k views

Code Solution for the Magic Hexagon [closed]

A magic hexagon is a hexagon where every row and every diagonal add up to the same value. In this case the value is 38. Each number from 1 to 19 must be used exactly once. Hexagon http://minortriad....
5
votes
1answer
2k views

Sudoku board generator

A program that randomly generates a Sudoku game board with varying degrees of difficulty (however you decide to measure difficulty). Sudoku requires that there is only one solution, so your program ...
10
votes
16answers
10k views

Random sampling without replacement

Create a function that will output a set of distinct random numbers drawn from a range. The order of the elements in the set is unimportant (they can even be sorted), but it must be possible for the ...
15
votes
5answers
2k views

Fastest Sort in BrainF***

After having implemented QuickSort in BrainF***, I realized it probably wasn't that quick. Operations that are O(1) in normal languages (like array indexing) are significantly longer in BF. Most of ...
2
votes
8answers
6k views

compute number of 1 bits in a binary representation of a number

The goal is to write a program that returns number of 1 bits in a given number. Examples 5 -> 2 1254 -> 6 56465 -> 8 Winner The winning ...
-7
votes
3answers
1k views

write a code the find n-th number of Gray Code list [closed]

Write a function that, given N >= 0, finds the Nth number in a standard Gray code. Example input: 1 2 3 4 Example output: ...
2
votes
13answers
865 views

position of the only 1 in a number in binary format [closed]

Every number of the form 2i (where i is a non-negative integer) has a single 1 in its binary representation. Given such a number, output the 1-based position of the ...
45
votes
3answers
3k views

Help Indiana Jones to get the treasure

Story Indiana Jones was exploring a cave where a precious treasure is located. Suddenly, an earthquake happened. When the earthquake ended, he noticed that some rocks that had fallen from the ...
2
votes
2answers
802 views

Fastest C/C++ comparison function for an opaque field containing doubles

Description: Write the fastest comparison function for an opaque field containing a double. Here is my example: ...
10
votes
12answers
4k views

Write the fastest Fibonacci

This is yet another challenge about the Fibonacci numbers. The goal is to compute the 20'000'000th Fibonacii number as fast as possible. The decimal output is about 4 MiB large; it starts with: ...
6
votes
3answers
2k views

Lottery Ball Problem

A woman works at a lottery ball factory. She's instructed to open up a lottery ball creation kit composed of 1 red rubber ball and n strips of digits from 0 through 9. She's instructed to do the ...
70
votes
23answers
11k views

Contest: fastest way to sort a big array of Gaussian-distributed data

Following the interest in this question, I thought it would be interesting to make answers a bit more objective and quantitative by proposing a contest. The idea is simple: I have generated a binary ...
14
votes
2answers
2k views

Fastest python code to find a set of winning words in this game

This is a word game from a set of activity cards for children. Below the rules is code to find the best triplet using /usr/share/dict/words. I thought it was an interesting optimization problem, and ...
5
votes
5answers
1k views

Code-Challenge: Farey sequence (II)

Challenge In this task you would be given an integer N (less than 10^6), output the number of terms in the Farey sequence of order N. The input N < 106 is given in a single line, the inputs ...
12
votes
1answer
752 views

Break the broken cipher

I have designed a simple random generator that cycles two numbers in a chaotic way using a multiply and modulus method. It works great for that. If I were to use it as a cipher generator it would ...
5
votes
3answers
3k views

Carmichael Numbers

EDIT: I am changing the challenge. Write a program to print Carmichael numbers. The challenge is to print the maximum number of them in less than 5 secs. The numbers should be in increasing order. ...
11
votes
5answers
649 views

Fast Topswops calculation

From AZSPCS: Suppose you have a deck containing n cards. Each card contains a number from 1 to n, and each number appears on exactly one card. You look at the number on the top card -- let's says it'...
9
votes
4answers
2k views

Fast line drawing algorithm

The task is to find a way to draw a horizontal line in an array of 16-bit integers. We're assuming a 256x192 pixel array with 16 pixels per word. A line is a contiguous run of set (1) bits. Lines ...