fix(curriculum): Fix a typo in 10-coding-interview-prep/rosetta-code/subleq (#44133)
* Fix a typo * Fix more new line issuespull/44148/head
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@ -10,28 +10,20 @@ dashedName: subleq
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[Subleq](https://rosettacode.org/wiki/eso:Subleq) is an example of a [One-Instruction Set Computer (OISC)](https://en.wikipedia.org/wiki/One_instruction_set_computer).
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It is named after its only instruction, which is **SU**btract and **B**ranch if **L**ess than or **EQ**ual
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to zero.
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It is named after its only instruction, which is **SU**btract and **B**ranch if **L**ess than or **EQ**ual to zero.
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Your task is to create an interpreter which emulates such a machine.
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The machine's memory consists of an array of signed integers. Any reasonable word size is fine, but the memory must be
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able to hold negative as well as positive numbers.
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The machine's memory consists of an array of signed integers. Any reasonable word size is fine, but the memory must be able to hold negative as well as positive numbers.
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Execution begins with the instruction pointer aimed at the first word, which is address 0. It proceeds as follows:
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<ol>
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<li>Let A, B, and C be the value stored in the three consecutive words in memory starting at the instruction pointer.</li>
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<li>Advance the instruction pointer 3 words to point at the address after the one containing C.</li>
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<li>If A is -1, then a character is read from standard input and its code point stored in the address given by B. C
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is unused.</li>
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<li>If B is -1, then the number contained in the address given by A is interpreted as a code point and the
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corresponding character output. C is again unused.</li>
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<li>Otherwise, both A and B are treated as the addresses of memory locations. The number contained in the address
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given by A is subtracted from the number at the address given by B (and the result stored back in address B). If
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the result is zero or negative, the value C becomes the new instruction pointer.</li>
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<li>If A is -1, then a character is read from standard input and its code point stored in the address given by B. C is unused.</li>
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<li>If B is -1, then the number contained in the address given by A is interpreted as a code point and the corresponding character output. C is again unused.</li>
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<li>Otherwise, both A and B are treated as the addresses of memory locations. The number contained in the address given by A is subtracted from the number at the address given by B (and the result stored back in address B). If the result is zero or negative, the value C becomes the new instruction pointer.</li>
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<li>If the instruction pointer becomes negative, execution halts.</li>
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</ol>
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@ -39,15 +31,7 @@ Other negative addresses besides -1 may be treated as equivalent to -1, or gener
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Your solution should accept a program to execute on the machine, separately from the input fed to the program itself.
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This program should be in raw subleq "machine code" - whitespace-separated decimal numbers, with no symbolic names or
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other assembly-level extensions, to be loaded into memory starting at address 0. Show the output of your solution when
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fed this "Hello, world!" program. (Note that the example assumes ASCII or a superset of it, such as any of the Latin-N
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character sets or Unicode. You may translate it into another character set if your implementation is on a
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non-ASCiI-compatible environment.)
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This program should be in raw subleq "machine code" - whitespace-separated decimal numbers, with no symbolic names or other assembly-level extensions, to be loaded into memory starting at address 0. Show the output of your solution when fed this "Hello, world!" program. (Note that the example assumes ASCII or a superset of it, such as any of the Latin-N character sets or Unicode. You may translate it into another character set if your implementation is on a non-ASCiI-compatible environment.)
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<pre>15 17 -1 17 -1 -1 16 1 -1 16 3 -1 15 15 0 0 -1 72 101 108 108 111 44 32 119 111 114 108 100 33 10 0</pre>
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@ -66,9 +50,7 @@ message: "Hello, world!\n\0"
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# --instructions--
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Write a function that takes an array of integers as a parameter. This represents the memory elements. The function
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should interpret the sequence and return the output string. For this task, assume that there is no standard input.
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Write a function that takes an array of integers as a parameter. This represents the memory elements. The function should interpret the sequence and return the output string. For this task, assume that there is no standard input.
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# --hints--
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