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Emil Bremer Orloff Dyalog14 Eastbourne, UK

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What will this be about Emil will describe his experiences of Dyalog and tell us how he managed to master enough of it to win the competition.

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What will this be about About me Relation to APL The competition

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About me Studying Computer Science at Aarhus University

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About me Studying Computer Science at Aarhus University

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About me Studying Computer Science at Aarhus University 4 years into my masters degree

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About me Studying Computer Science at Aarhus University 4 years into my masters degree Specialized in Cryptography and programming languages Programming experience in: Java, Ocaml, SML, C, Coq, (Matlab)

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My first encounter with APL

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2011: my department shared a link to the Dyalog Competition

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My first encounter with APL 2011: my department shared a link to the Dyalog Competition A horrible mess of funny characters!

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My first encounter with APL 2011: my department shared a link to the Dyalog Competition A horrible mess of funny characters! Became interessted due to the nature of the language had to use another approach Didnt have time to learn

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Fastforward 2014 Last chance to compete as a student

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Fastforward 2014 Last chance to compete as a student Legrands book

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The Competition Phase 1 10 problems solved using dfns Here follows a couple of my solutions

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Problem 5 - Mirror Mirror Tell if a given strings is a palidrome

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Problem 5 - Mirror Mirror Tell if a given strings is a palidrome Nave: { }

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Problem 5 - Mirror Mirror Tell if a given strings is a palidrome Nave: { } Unfortunately only letters are relevant

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Problem 5 - Mirror Mirror Tell if a given strings is a palidrome Nave: { } Unfortunately only letters are relevant {{ }( 'abcdefghijklmnopqrs tuvwxyzABCDEFGHIJKLMNOPQRSTUVWX YZ')/ }

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Problem 8- Go the distance Find the distance between two points in n- dimensional space

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Problem 8- Go the distance Find the distance between two points in n- dimensional space {(+/( - )*2)*0.5}

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Part II Consisted of 3 problem sets Each containing 3 parts (easy, medium, hard)

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Part II Consisted of 3 problem sets Each containing 3 parts (easy, medium, hard) Bioinformatics Cryptography Recreation and games

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Part II Consisted of 3 problem sets Each containing 3 parts (easy, medium, hard) Bioinformatics (easy, medium, hard) Cryptography (easy, hard) Recreation and Games (hard)

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Bioinformatics K-mer counting Most frequent k-mers Clump finding Approximate pattern matching Shared k-mers Longest shared substring Shortest non-shared substring Edit distance

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Bioinformatics K-mer counting Most frequent k-mers Clump finding Approximate pattern matching Shared k-mers Longest shared substring Shortest non-shared substring Edit distance

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Bioinformatics K-mer counting Most frequent k-mers Clump finding Approximate pattern matching Shared k-mers Longest shared substring Shortest non-shared substring Edit distance Substringsand

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Substring Created a helper function that could create all substrings of a given length

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Substring Created a helper function that could create all substrings of a given length Create all relevant indexes

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Substring Created a helper function that could create all substrings of a given length Creating all relevant indexes

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Substring Created a helper function that could create all substrings of a given length Creating all relevant indexes Use N-Wise reduce! { > :'' ,/ } Changed shortly before deadline

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Bioinformatics K-mer counting Most frequent k-mers Clump finding Approximate pattern matching Shared k-mers Longest shared substring Shortest non-shared substring Edit distance SubstringsAnd

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Edit distance Given two strings find the minimal edits that brings the first to the second An edit: Insert a character Delete a character

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Edit distance Generate a matrix that gives the editdistance between the substrings

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Edit distance Generate a matrix that gives the editdistance between the substrings manly 012345 m101234 a210123 n321012 y432111

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Edit distance Generate a matrix that gives the editdistance between the substrings manly 012345 m101234 a210123 n321012 y432111 First row and first column are always the same

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Edit distance Each element in table is given by 0+value to NW if the characters match 1+the minimum value to the W, NW or N if the characters does not match

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Edit distance Each element in table is given by 0+value to NW if the characters match 1+the minimum value to the W, NW or N if the characters does not match Which is min(cost+NW, 1+W, 1+N)

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Edit distance firstRow( 1+ t)-1

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Edit distance firstRow( 1+ t)-1 nextRow{ {( +1) }\(1+ ) (1+ ),(1 )+ t }

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Edit distance firstRow( 1+ t)-1 nextRow{ {( +1) }\(1+ ) (1+ ),(1 )+ t } lastRow nextRow/( s), firstRow ed lastRow

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Edit distance firstRow( 1+ t)-1 nextRow{ {( +1) }\(1+ ) (1+ ),(1 )+ t } lastRow nextRow/( s), firstRow ed lastRow

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What was actually delivered

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Cryptography Viginre cipher Book cipher variation Playfair cipher

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Cryptography Viginre cipher Book cipher variation Playfair cipher

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Recreation and Games Word search Scrabble Bridge

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Recreation and Games Word search Scrabble Bridge

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