---
title: Execute a Markov algorithm
id: 59e09e6d412c5939baa02d16
challengeType: 5
videoUrl: ''
localeTitle: ''
---

## Description
undefined

## Instructions
undefined

## Tests
<section id='tests'>

```yml
tests:
  - text: ''
    testString: 'assert(typeof markov === "function", "<code>markov</code> is a function.");'
  - text: ''
    testString: 'assert.deepEqual(markov(rules[0],tests[0]),outputs[0],"<code>markov(["A -> apple","B -> bag","S -> shop","T -> the","the shop -> my brother","a never used -> .terminating rule"],"I bought a B of As from T S.")</code> should return "I bought a bag of apples from my brother.".");'
  - text: ''
    testString: 'assert.deepEqual(markov(rules[1],tests[1]),outputs[1],"<code>markov(["A -> apple","B -> bag","S -> .shop","T -> the","the shop -> my brother","a never used -> .terminating rule"],"I bought a B of As from T S.")</code> should return "I bought a bag of apples from T shop.".");'
  - text: ''
    testString: 'assert.deepEqual(markov(rules[2],tests[2]),outputs[2],"<code>markov(["A -> apple","WWWW -> with","Bgage -> ->.*","B -> bag","->.* -> money","W -> WW","S -> .shop","T -> the","the shop -> my brother","a never used -> .terminating rule"],"I bought a B of As W my Bgage from T S.")</code> should return "I bought a bag of apples with my money from T shop.".");'
  - text: ''
    testString: 'assert.deepEqual(markov(rules[3],tests[3]),outputs[3],"<code>markov(["_+1 -> _1+","1+1 -> 11+","1! -> !1",",! -> !+","_! -> _","1*1 -> x,@y","1x -> xX","X, -> 1,1","X1 -> 1X","_x -> _X",",x -> ,X","y1 -> 1y","y_ -> _","1@1 -> x,@y","1@_ -> @_",",@_ -> !_","++ -> +","_1 -> 1","1+_ -> 1","_+_ -> "],"_1111*11111_")</code> should return "11111111111111111111".");'
  - text: ''
    testString: 'assert.deepEqual(markov(rules[4],tests[4]),outputs[4],"<code>markov(["A0 -> 1B","0A1 -> C01","1A1 -> C11","0B0 -> A01","1B0 -> A11","B1 -> 1B","0C0 -> B01","1C0 -> B11","0C1 -> H01","1C1 -> H11"],"")</code> should return "00011H1111000".");'

```

</section>

## Challenge Seed
<section id='challengeSeed'>

<div id='js-seed'>

```js
function markov (rules,test) {
  // Good luck!
}

```

</div>



</section>

## Solution
<section id='solution'>

```js
// solution required
```
</section>