HQ0-9+-INCOMPUTABLE?!
Time limit1sMemory limit1024 MB
Construct an HQ0-9+-INCOMPUTABLE?! program of at most 10000 commands whose final buffer equals a given target string.
- Level
Hard10 of 10
- Topics
- String, Simulation, Implementation, Brute force
- Solved
- No attempts yet
Problem
HQ9+ is an esoteric programming language specialized for certain tasks. For example, printing "Hello, world!" or writing a quine (a program that prints itself) could not be any simpler. Unfortunately, HQ9+ does not do very well in most other situations. This is why we have created our own variant of the language, HQ0-9+-INCOMPUTABLE?!.
An HQ0-9+-INCOMPUTABLE?! program is a sequence of commands, written on one line without any whitespace (except for the trailing newline). The program can store data in two memory areas: the buffer, a string of characters, and the accumulator, an integer variable. Initially, the buffer is empty and the accumulator is set to 0. The value of the buffer after executing all the commands becomes the program's output.
HQ0-9+-INCOMPUTABLE?! supports the following commands:
| `?` | removes 47 characters from the end of the buffer (or everything if it is too short) |
| `!` | removes 47 characters from the beginning of the buffer (or everything if it is too short) |
As you can see, HQ0-9+-INCOMPUTABLE?! is much more powerful than HQ9+. Demonstrate this by writing and submitting an HQ0-9+-INCOMPUTABLE?! program that outputs 로그인하면 보이는 값.
Constraints
Your program must be at most 10000 commands long. The accumulator is unbounded (it can store an arbitrarily large integer). After each command, the buffer must be at most 10000 characters long. To prevent code injection vulnerabilities, during the execution of your program the buffer must never contain non-alphanumeric characters, i.e. characters other than A-Z, a-z, and 0-9. Should this happen, the program fails with a runtime error, and your submission will be rejected.