Seek to find the longest simple computer program

But how difficult? In 1962, the mathematics world invented a new way to explore this question through what he called Poor beaver game. To play, start choosing a specific number of rules – this number N. Your goal is to find NThe Torring machine that runs the longest before it stops at the end. This mixed degenerate device, the compassionate beaver number, BB (N), The number of steps required.

In principle, if you want to find a crowded beaver for any specific person NYou just need to do some things. First, list everything possible NTorring machines. After that, use a computer program to simulate the operation of each device. Look for Telltale signs that the machines will never stop – for example, many machines will fall into unlimited repeated rings. Ignore all these unnamed machines. Finally, record the number of steps taken by each other machine before stopping. A person with the longest operation time is your crowded jands.

In practice, this becomes difficult. For beginners, the number of possible machines grows rapidly with each new base. It will all be a hopeless individually from it, so you will need to write a computer program dedicated to classifying and ignoring machines. It is easy to classify some machines: either they stop quickly or fall into endless episodes that can be easily recognized. But others run for a long time without width any clear pattern. For these machines, the stopping problem deserves its frightening reputation.

The more the rules you add, the more computing you need. But brute force is not enough. Some machines work for a long time before stopping simulating them step by step impossible. You need smart sporty tricks to measure their operating times.

“Technological improvements definitely help,” he said Sean LegukiSoftware engineer and Hintter Bever for a long time. “But they only help now.”

The end of the era

The fishermen in the busy gun started cutting the BB (6) problem seriously in the 1990s and Finets, during a dilemma in the BB (5) pursuit. Among them is Sean Leguki and his father, Terry, the Applied Mathematics Scientist who managed the research program for working hours on strong computers at the Lawrence Berkeley National Laboratory. In 2007, they found the Six -story Torring machine that shattered the record for the longest operating time: the number of steps I took before stopping it has approximately 3000 numbers. This is a huge number through any ordinary scale. But it is not necessary to write. In the 12 -point line, those number 3000 numbers will cover approximately one sheet.

In 2022, Shawn Ligocki discovered the Torring machine six its edges at the time of operation of more than the number of atoms in the universe.

Photo: Keira Triberg

Three years later, a student of computer science in Slovak university students called Pavel Kruptz decided to handle the BB (6) chase as a large thesis project. Its research program has written and prepared for operation in the background on a 30 -computer network in a university laboratory. A month later, he found a machine that lasted much longer than the new Ligockis – “hero”, in the language of Baver Beaver.

“I was lucky, because people in the laboratory were already complaining about the use of my CPU and I had to expand a little,” Krovz wrote in the exchange of direct messages on Discord Challenge. After another month of search, his own record was broken with a machine that was operating more than 30,000 number – filling about 10 pages.