Add solution 423

Author: vulgur

Diff for: 423_ReconstructOriginalDigitsFromEnglish.swift

@@ -0,0 +1,96 @@
+class Solution {
+    func originalDigits(_ s: String) -> String {
+        let letters:[Character:Int] = [
+            "z":0,
+            "x":6,
+            "w":2,
+            "u":4,
+            "g":8,
+            "t":3,
+            "f":5,
+            "s":7,
+            "o":1,
+            "n":9]
+        
+        var map = [Character: Int]()
+        var result = [Int]()
+        for c in s {
+            map[c] = (map[c] ?? 0) + 1
+        }
+        for letter in "zxwugtfso" {
+            if let count = map[letter] {
+                reduceWords(letter, count, &map)
+                result += Array(repeating:letters[letter]!, count:count)
+            }
+        }
+        
+        if let count = map["e"] {
+            result.append(contentsOf: Array(repeating:9, count:count))
+        }
+        
+        var returnValue = ""
+        for i in result.sorted() {
+            returnValue +=  "\(i)"
+        }
+        return returnValue
+    }
+
+    func reduceWords(_ letter: Character, _ n:Int, _ map: inout [Character:Int]) {
+        switch letter {
+            case "z"://zero
+                reduceLetters("z", n, &map)
+                reduceLetters("e", n, &map)
+                reduceLetters("r", n, &map)
+                reduceLetters("o", n, &map)
+            case "x"://six
+                reduceLetters("s", n, &map)
+                reduceLetters("i", n, &map)
+                reduceLetters("x", n, &map)
+            case "w":
+                reduceLetters("t", n, &map)
+                reduceLetters("w", n, &map)
+                reduceLetters("o", n, &map)
+            case "u":
+                reduceLetters("f", n, &map)
+                reduceLetters("o", n, &map)
+                reduceLetters("u", n, &map)
+                reduceLetters("r", n, &map)
+            case "g":
+                reduceLetters("e", n, &map)
+                reduceLetters("i", n, &map)
+                reduceLetters("g", n, &map)
+                reduceLetters("h", n, &map)
+                reduceLetters("t", n, &map)
+            case "t":
+                reduceLetters("t", n, &map)
+                reduceLetters("h", n, &map)
+                reduceLetters("r", n, &map)
+                reduceLetters("e", n*2, &map)
+            case "f":
+                reduceLetters("f", n, &map)
+                reduceLetters("i", n, &map)
+                reduceLetters("v", n, &map)
+                reduceLetters("e", n, &map)
+            case "s":
+                reduceLetters("s", n, &map)
+                reduceLetters("e", n*2, &map)
+                reduceLetters("v", n, &map)
+                reduceLetters("n", n, &map)
+            case "o":
+                reduceLetters("o", n, &map)
+                reduceLetters("n", n, &map)
+                reduceLetters("e", n, &map)
+            default:
+                return
+        }
+        
+    }
+        
+    func reduceLetters(_ letter: Character, _ n:Int, _ map: inout [Character: Int]) {
+        if let count = map[letter] {
+            map[letter] = count-n
+        }
+    }
+}
+
+