README.md (1521B) - raw
1 # Nucleotide Count 2 3 Welcome to Nucleotide Count on Exercism's Perl 5 Track. 4 If you need help running the tests or submitting your code, check out `HELP.md`. 5 6 ## Instructions 7 8 Each of us inherits from our biological parents a set of chemical instructions known as DNA that influence how our bodies are constructed. All known life depends on DNA! 9 10 > Note: You do not need to understand anything about nucleotides or DNA to complete this exercise. 11 12 DNA is a long chain of other chemicals and the most important are the four nucleotides, adenine, cytosine, guanine and thymine. A single DNA chain can contain billions of these four nucleotides and the order in which they occur is important! 13 We call the order of these nucleotides in a bit of DNA a "DNA sequence". 14 15 We represent a DNA sequence as an ordered collection of these four nucleotides and a common way to do that is with a string of characters such as "ATTACG" for a DNA sequence of 6 nucleotides. 16 'A' for adenine, 'C' for cytosine, 'G' for guanine, and 'T' for thymine. 17 18 Given a string representing a DNA sequence, count how many of each nucleotide is present. 19 If the string contains characters that aren't A, C, G, or T then it is invalid and you should signal an error. 20 21 For example: 22 23 ``` 24 "GATTACA" -> 'A': 3, 'C': 1, 'G': 1, 'T': 2 25 "INVALID" -> error 26 ``` 27 28 ## Source 29 30 ### Created by 31 32 - @bentglasstube 33 34 ### Contributed to by 35 36 - @kytrinyx 37 - @m-dango 38 - @rfilipo 39 40 ### Based on 41 42 The Calculating DNA Nucleotides_problem at Rosalind - http://rosalind.info/problems/dna/