19 questions linked to/from PPCG Jeopardy: Robbers
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### Shortest infinite loop producing no output

Your task is to create the shortest infinite loop! The point of this challenge is to create an infinite loop producing no output, unlike its possible duplicate. The reason to this is because the code ...
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### Implement a Truth-Machine

A truth-machine (credits goes to this guy for coming up with it) is a very simple program designed to demonstrate the I/O and control flow of a language. Here's what a truth-machine does: Gets a ...
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### What is the smallest positive base 10 integer that can be printed by a program shorter (in characters) than itself?

I think the question as above is clear, but just in case: Write a full program (not just a function) which prints a positive base 10 integer, optionally followed by a single newline. Qualifying ...
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### Print every character your program doesn't have

Your task is to build a program (using only printable ASCII characters and/or tabs and newlines) that prints out exactly the characters in the printable ASCII space (...
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### Print the ASCII table

The task is to display n characters of the ASCII table. You may write a function (or a program that takes the argument as a parameter, STDIN is allowed as well) that takes a parameter n, which will ...
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### PPCG Jeopardy: Cops

How well do you know the site? Let's find out. This is a cops-and-robbers challenge. Robber's thread. As a cop, you need to: Find a non-deleted, non-closed challenge on this site to answer. The ...
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### Natural construction

The natural numbers including 0 are formally defined as sets, in the following way: Number 0 is defined as the empty set, {} For n ≥ 0, number n+1 is defined as n ∪ {n}. As a consequence, n = {0, 1, ...
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### Different Way Forward

Given a list of integers produce a Forward Difference at a specified order/depth. For the list of integers: (10, 18, -12, 4, 8, -3, -5, 67, 9, 14) The Forward ...
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### Substring Sum Set

Introduction Let's observe this array: [3, 2, 4, 1, 1, 5, 1, 2]. Each element displays the length of the substring which must be summed up. Let's take a look at ...
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### Use xkcd's formula to approximate the world population

In xkcd 1047, Randall Munroe lists "slightly wrong" approximations of assorted quantities and numbers with varying precision and complexity, such as that the number of liters in a gallon is very close ...
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### "Convenient palindrome" checker

If you've ever tried to write palindromic code before, you'd know how much brackets tend to get in your way. ()() is not a palindrome, even though it kinda looks ...
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### Keep the unique characters down

It's very simple: Your program or function should generate the following text: ...
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### Calculate hamming weight with low hamming weight

Create a program that computes the hamming weight of a string. Winner is the program with the lowest hamming weight. Rules: Hamming weight for an ASCII character is defined as the total number of ...
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### Evaluating the score based from a chess FEN string

Challenge Forsyth–Edwards Notation (FEN) is a standard notation for describing a particular board position of a chess game. Your challenge is to evaluate the score using the FEN string. This is an ...
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