Advent of Code in Kotlin: Lessons Learned

Transcript

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3. Photo by Elena Mozhvilo on Unsplash Photo by Markus Spiske

   on Unsplash
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16. 2020 Unofficial Advent of Code Survey - Jeroen Heijmans

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18. Daniel Lin (@ephemient) Solved every daily puzzle in four different

    languages. ephemient.github.io/aoc2020/

19. Joris Portegies Zwart (@jorispz) Solves puzzles using Kotlin Multiplatform. github.com/jorispz/aoc-2020

20. Jakub Gwóźdź Solved every puzzle and provided a visualization. In

    Kotlin! jakubgwozdz.github.io/advent-of- code-2020/

21. Courtesy of @FuriousProgramm @FuriousProgramm Also attempting to solve this puzzle.

    Manually.

22. Since 2017, I have solved each puzzle each day, in

    Kotlin and blogged about it. https://todd.ginsberg.com
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25. val letters = listOf("A", "B", "C", "D") val numbers =

    listOf(1, 2, 3, 4)

26. val letters = listOf("A", "B", "C", "D") val numbers =

    listOf(1, 2, 3, 4) letters.zip(numbers) // [(A, 1), (B, 2), (C, 3), (D, 4)] // List<Pair<String,Int>>

27. val letters = listOf("A", "B", "C", "D")

28. val letters = listOf("A", "B", "C", "D") letters.zipWithNext() // [(A,

    B), (B, C), (C, D)] // List<Pair<String,String>>

29. val letters = listOf("A", "B", "C", "D")

30. val letters = listOf("A", "B", "C", "D") letters.chunked(2) // [[A,

    B], [C, D]] // List<List<String>>

31. val letters = listOf("A", "B", "C", "D", "E", "F")

32. val letters = listOf("A", "B", "C", "D", "E", "F") letters.windowed(3)

    // [[A, B, C], [B, C, D], [C, D, E], [D, E, F]] // List<List<String>>

33. val letters = listOf("A", "B", "C", "D", "E", "F") letters.windowed(3,

    3) // [[A, B, C], [D, E, F]]

34. val letters = listOf("A", "B", "C", "D", "E", "F") letters.windowed(4,

    4, false) // [[A, B, C, D]]

35. val theString = "Hello" theString.padEnd(7, '!') // Hello!!

36. val theString = "Hello" theString.padStart(7, '!') // !!Hello

37. val theString = "Left Right"

38. val theString = "Left Right" theString.substringBefore(" ") // "Left"

39. val theString = "Left Right" theString.substringBefore(" ") // "Left" theString.substringAfter("

    ") // "Right"

40. val someList = listOf("A", "B", "C")

41. val someList = listOf("A", "B", "C") someList.any { it.length ==

    1 } // True!

42. val someList = listOf("A", "B", "C") someList.all { it.length ==

    1 } // True!

43. val someList = listOf("A", "B", "C") someList.none { it.length ==

    2 } // True!

44. "3".toInt() // 3

45. "3".toInt() // 3 '3'.toInt() // 51

46. fun Char.asInt(): Int = this.toString().toInt()

47. fun Char.asInt(): Int = this.toString().toInt() '3'.asInt() // 3

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