Data commit

Task/Letter-frequency/Swift/letter-frequency.swift

@@ -0,0 +1,19 @@
+import Foundation
+
+let dictPath: String
+
+switch CommandLine.arguments.count {
+case 2:
+  dictPath = CommandLine.arguments[1]
+case _:
+  dictPath = "/usr/share/dict/words"
+}
+
+let wordsData = FileManager.default.contents(atPath: dictPath)!
+let allWords = String(data: wordsData, encoding: .utf8)!
+let words = allWords.components(separatedBy: "\n")
+let counts = words.flatMap({ $0.map({ ($0, 1) }) }).reduce(into: [:], { $0[$1.0, default: 0] += $1.1 })
+
+for (char, count) in counts {
+  print("\(char): \(count)")
+}