2020-02-26 20:21:42 +01:00
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# Look-and-Say
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2020-02-19 01:11:58 +01:00
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2020-02-21 00:34:07 +01:00
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## Goal
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2020-04-16 21:09:34 +02:00
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Given an `iteration-count` generate and output the `look-and-say` sequence.
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The sequence starts with `1`. Subsequent numbers are derived by describing the previous number in terms of consecutive digits.
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To generate an entry of the sequence, examine the previous entry.
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Read off the digits of the previous entry, counting the number of digits in groups of the same digit.
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2020-02-19 01:11:58 +01:00
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In human terms this is like speaking out loud how often each digit appears consecutively.
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2020-04-16 21:09:34 +02:00
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**Keep in mind:** the output becomes very long very quickly.
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2020-02-21 00:34:07 +01:00
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### Input
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2020-02-19 01:11:58 +01:00
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`iterations` - a numeric value how often the process is repeated
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2020-02-21 00:34:07 +01:00
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### Output
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2020-04-16 21:09:34 +02:00
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The head of the generated sequence after iterating by the given input.
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2020-02-19 01:11:58 +01:00
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2020-02-21 00:34:07 +01:00
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### Constraints
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2020-04-16 21:09:34 +02:00
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* 0 <= `iterations` <= 28
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* **Start value** = 1
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2020-02-19 01:11:58 +01:00
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2020-02-21 00:34:07 +01:00
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### Examples
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2020-04-16 21:09:34 +02:00
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* for input `0` iterations, output `1`, i.e. the starting value)
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* for input `1` iterations, output `11`, i.e. reading the previous entry `1` as `one 1`
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* for input `2` iterations, output `21`, i.e. reading the previous entry `11` as `two 1s`
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* for input `3` iterations, output `1211`, i.e. reading the previous entry `21` as `one 2 one 1`
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* for input `4` iterations, output `111221`, i.e. reading the previous entry `1211` as `one 1 one 2 two 1`
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