# 99 questions/80 to 89

This is part of Ninety-Nine Haskell Problems, based on Ninety-Nine Prolog Problems.

If you want to work on one of these, put your name in the block so we know someone's working on it. Then, change n in your block to the appropriate problem number, and fill in the <Problem description>,<example in lisp>,<example in Haskell>,<solution in haskell> and <description of implementation> fields.

## Problem 80

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>

## Problem 81

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>

## Problem 82

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>

## Problem 83

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>

## Problem 84

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>

## Problem 85

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>

## Problem 86

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>

## Problem 87

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>

## Problem 88

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>

## Problem 89

<Problem description>

```Example:
<example in lisp>

```

Solution:

```<solution in haskell>
```

<description of implementation>