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Feat: add new Markdown parser (#39800)

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and change all the challenges to new `md` format.
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Oliver Eyton-Williams
2020-11-27 19:02:05 +01:00
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commit 0bd52f8bd1
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curriculum/challenges/english/10-coding-interview-prep/rosetta-code/execute-brain.md
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@ -1,70 +1,68 @@
---
title: Execute Brain****
id: 59e0a8df964e4540d5abe599
title: Execute Brain****
challengeType: 5
forumTopicId: 302261
---
## Description
<section id='description'>
Write a function to implement a Brain**** interpreter. The function will take a string as a parameter and should return a string as the output. More details are given below:
RCBF is a set of <a href="https://rosettacode.org/wiki/Brainf***" title="Brainf***" target="_blank">Brainf***</a> compilers and interpreters written for Rosetta Code in a variety of languages.
# --description--
Write a function to implement a Brain\*\*\*\* interpreter. The function will take a string as a parameter and should return a string as the output. More details are given below:
RCBF is a set of [Brainf\*\*\*](https://rosettacode.org/wiki/Brainf*** "Brainf\*\*\*") compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly implement the following instructions:
| Command | Description |
| --- | --- |
| <code>&gt;</code> | Move the pointer to the right |
| <code>&lt;</code> | Move the pointer to the left |
| <code>+</code> | Increment the memory cell under the pointer |
| <code>-</code> | Decrement the memory cell under the pointer |
| <code>.</code> | Output the character signified by the cell at the pointer |
| <code>,</code> | Input a character and store it in the cell at the pointer |
| <code>[</code> | Jump past the matching <code>]</code> if the cell under the pointer is 0 |
| <code>]</code> | Jump back to the matching <code>[</code> if the cell under the pointer is nonzero |
Any cell size is allowed, EOF (<u>E</u>nd-<u>O</u>-<u>F</u>ile) support is optional, as is whether you have bounded or unbounded memory.
</section>
| Command | Description |
| ----------------- | ---------------------------------------------------------------------------------- |
| <code>></code> | Move the pointer to the right |
| <code>&lt;</code> | Move the pointer to the left |
| <code>+</code> | Increment the memory cell under the pointer |
| <code>-</code> | Decrement the memory cell under the pointer |
| <code>.</code> | Output the character signified by the cell at the pointer |
| <code>,</code> | Input a character and store it in the cell at the pointer |
| <code>\[</code> | Jump past the matching <code>]</code> if the cell under the pointer is 0 |
| <code>]</code> | Jump back to the matching <code>\[</code> if the cell under the pointer is nonzero |
## Instructions
<section id='instructions'>
Any cell size is allowed, EOF (*E*nd-*O*-*F*ile) support is optional, as is whether you have bounded or unbounded memory.
</section>
# --hints--
## Tests
<section id='tests'>
```yml
tests:
- text: <code>brain(bye)</code> should return a string
testString: assert(typeof brain(bye) === 'string');
- text: <code>brain("++++++[>++++++++++<-]>+++++.")</code> should return "A"
testString: assert.equal(brain("++++++[>++++++++++<-]>+++++."),"A");
- text: <code>brain(bye)</code> should return <code>Goodbye, World!\\r\\n</code>
testString: assert.equal(brain(bye), 'Goodbye, World!\r\n');
- text: <code>brain(hello)</code> should return <code>Hello World!\\n</code>
testString: assert.equal(brain(hello), "Hello World!\n");
- text: <code>brain(fib)</code> should return <code>1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89</code>
testString: assert.equal(brain(fib), "1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89");
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
`brain(bye)` should return a string
```js
function brain(prog) {
}
assert(typeof brain(bye) === 'string');
```
</div>
`brain("++++++[>++++++++++<-]>+++++.")` should return "A"
### Before Test
<div id='js-setup'>
```js
assert.equal(brain('++++++[>++++++++++<-]>+++++.'), 'A');
```
`brain(bye)` should return `Goodbye, World!\r\n`
```js
assert.equal(brain(bye), 'Goodbye, World!\r\n');
```
`brain(hello)` should return `Hello World!\n`
```js
assert.equal(brain(hello), 'Hello World!\n');
```
`brain(fib)` should return `1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89`
```js
assert.equal(brain(fib), '1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89');
```
# --seed--
## --before-user-code--
```js
let fib=`+
@ -134,19 +132,20 @@ let hello='++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++
let bye='++++++++++[>+>+++>++++>+++++++>++++++++>+++++++++>++++++++++>+++++++++++>++++++++++++<<<<<<<<<-]>>>>+.>>>>+..<.<++++++++.>>>+.<<+.<<<<++++.<++.>>>+++++++.>>>.+++.<+++++++.--------.<<<<<+.<+++.---.';
```
</div>
## --seed-contents--
```js
function brain(prog) {
</section>
## Solution
<section id='solution'>
}
```
# --solutions--
```js
function brain(prog){
var output="";
var code; // formatted code
var code; // formatted code
var ip = 0; // current instruction within code
var nest = 0; // current bracket nesting (for Out button)
var ahead = []; // locations of matching brackets
@ -156,50 +155,47 @@ function brain(prog){
var inp = 0; // current input character (fetch with ,)
var quit = 0;
var commands = {
'>':function() { if (++dp >= data.length) data[dp]=0 },
'<':function() { if (--dp < 0) quit++ },
'+':function() { ++data[dp] },
'-':function() { --data[dp] },
'[':function() { if (!data[dp]) ip = ahead[ip]; else ++nest },
']':function() { if ( data[dp]) ip = ahead[ip]; else --nest },
',':function() {
var c = document.getElementById("input").value.charCodeAt(inp++);
data[dp] = isNaN(c) ? 0 : c; // EOF: other options are -1 or no change
},
'.':function() {
output+=String.fromCharCode(data[dp]);
/*var s = document.getElementById("output").innerHTML)
+ String.fromCharCode(data[dp]);
s = s.replace(/\n/g,"<br>").replace(/ /g,"&amp;nbsp;");
document.getElementById("output").innerHTML = s;*/
},
var commands = {
'>':function() { if (++dp >= data.length) data[dp]=0 },
'<':function() { if (--dp < 0) quit++ },
'+':function() { ++data[dp] },
'-':function() { --data[dp] },
'[':function() { if (!data[dp]) ip = ahead[ip]; else ++nest },
']':function() { if ( data[dp]) ip = ahead[ip]; else --nest },
',':function() {
var c = document.getElementById("input").value.charCodeAt(inp++);
data[dp] = isNaN(c) ? 0 : c; // EOF: other options are -1 or no change
},
'.':function() {
output+=String.fromCharCode(data[dp]);
/*var s = document.getElementById("output").innerHTML)
+ String.fromCharCode(data[dp]);
s = s.replace(/\n/g,"<br>").replace(/ /g,"&amp;nbsp;");
document.getElementById("output").innerHTML = s;*/
},
};
let ar=prog.split('');
var st = [], back, error = -1;
for (ip=0; ip<ar.length; ip++) {
switch(ar[ip]) {
case '[':
st.push(ip);
break;
case ']':
if (st.length == 0) error = ip;
back = st.pop();
ahead[ip] = back;
ahead[back] = ip;
break;
}
}
let ar=prog.split('');
var st = [], back, error = -1;
for (ip=0; ip<ar.length; ip++) {
switch(ar[ip]) {
case '[':
st.push(ip);
break;
case ']':
if (st.length == 0) error = ip;
back = st.pop();
ahead[ip] = back;
ahead[back] = ip;
break;
}
}
for(ip=0;ip<ar.length;ip++){
for(ip=0;ip<ar.length;ip++){
if(commands.hasOwnProperty(ar[ip]))
commands[ar[ip]]();
}
commands[ar[ip]]();
}
return output;
return output;
}
```
</section>