I define the method of combining a sequence to mean that every number in the sequence is concatenated as a string, then that result is made an integer.
[1, 2, 3] -> 123
For every finite sequence of at least 3 consecutive integers, missing exactly one element in the sequence, and this missing e...
Imagine getting up for an urgent meeting, grabbing that towel, rushing to the bathroom in a hurry and end up finding that there’s no water in the tap. You try to find the reason behind it and you discover that the pipe got blocked. You think of taking your bath at your friend’s place but that’s n...
How many countries are in the European Union?
On 31 January 2020, the United Kingdom will leave the European Union, the first time that the number of EU member states will decrease.
Your job is to take a date (in any format) and output the number of members of the EU on that date, according to...
@PostRockGarfHunter Generally gvim because I'm on windows
But like... The real gvim, not ngvim or whatever it's called
I got really excited about neovim a few years ago, but then vim 8 came out and implemented a lot of the features that neovim was hyping, so I don't see the point as much.
I'm sure if I was writing games in vim I'd be pretty excited about nvim still
Inspired by a question on the puzzling stack exchange.
Rules
Given 5 stacks of 5 cards numbered 1 to 7, output the moves needed to empty all stacks. A move is defined as the index of a column to pull the card off of, and a move is only valid if:
The stack is non-empty
The value of the card ...
Background
We define the prime-counting function, \$\pi(x)\$, as the number of prime numbers less than or equal to \$x\$. You can read about it here.
For example, \$\pi(2) = 1\$ and \$\pi(6) = 3\$.
It can be shown, using dark magic, that
\$ \lim_{x \to \infty} \frac{\pi(x)}{x/\log x} = 1 \$
...
CMC: functional square root of cumulative sum. 1 1 1 1 1 → 1 1.5 1.875 2.1875 2.4609375; 1 1.5 1.875 2.1875 2.4609375 → 1 2 3 4 5; 3 1 4 1 5 9 2 6 → 3 2.5 5.625 4.3125 8.1328125 14.13671875 10.7041015625 14.04931640625 (i don't have (anything close to) a proof that my solution is the only one (or that it's even correct), but it was a fun challenge to get it at least working)
In Julia, how can I create a random binary array of b bits? I want something packed, as it were, so I can XOR it with other random binary array of b bits.
@Adám for a bit string, Print(StringMap(InputNumber(), Random(2))) (4 bytes in native Charcoal; if you were going to calculate on the array, you would probably use Map instead). for an arbitrary precision integer, Print(Cast(Random(Power(2, InputNumber())))) (5 bytes in native Charcoal; not sure whether Random actually works on arbitrary precision integers; not sure whether Charcoal has bitwise XOR anyway)
a linear-algebra solution: +\ is like matrix-multiplying by a matrix that has 0 above the diagonal and 1 on and below the diagonal. find its matrix square root and multiply by that instead
I actually just finished compiling a list of desired inverses. I plan on submitting it to Marshall for implementation asap, though he says he's unlikely to do it before 18.0.
E.g. ∘.f⍨⍣¯1 fails even though it is obviously f⍨⍣¯1⊢⍉⍨⍴∘⍴⍴∘⍳2÷⍨⍴∘⍴
@Bubbler Well think about it. ∘.f is an f-table. Now since we have ∘.f⍨ we know that the arguments listed down along the left side of the table are identical to the ones listed across the top. So along the diagonal, we have all the f⍨xs. This means that the original arguments are simply f⍨⍣¯1 on the diagonal.
I define the method of combining a sequence to mean that every number in the sequence is concatenated as a string, then that result is made an integer.
[1, 2, 3] -> 123
For every finite sequence of at least 3 consecutive integers, missing exactly one element in the sequence, and this missing e...
How many countries are in the European Union?
On 31 January 2020, the United Kingdom will leave the European Union, the first time that the number of EU member states will decrease.
Your job is to take a date (in any format) and output the number of members of the EU on that date, according to...
Inspired by a question on the puzzling stack exchange.
Rules
Given 5 stacks of 5 cards numbered 1 to 7, output the moves needed to empty all stacks. A move is defined as the index of a column to pull the card off of, and a move is only valid if:
The stack is non-empty
The value of the card ...
Background
We define the prime-counting function, \$\pi(x)\$, as the number of prime numbers less than or equal to \$x\$. You can read about it here.
For example, \$\pi(2) = 1\$ and \$\pi(6) = 3\$.
It can be shown, using dark magic, that
\$ \lim_{x \to \infty} \frac{\pi(x)}{x/\log x} = 1 \$
...
