Implement day 17, in swift.

2017/README.md

@@ -31,5 +31,6 @@ The current plan, in no particular order:
 - [x] Scala - [Day 11](./day-11/solution.scala)
 - [ ] Scheme
 - [ ] SQL
+- [ ] Swift - [Day 17](./day-17/solution.swift)
 
 … and then I will need some more. But that will come in time.

2017/day-17/.gitignore

@@ -0,0 +1 @@
+solution

2017/day-17/solution.swift

@@ -0,0 +1,25 @@
+let input = Int(readLine()!)!
+
+var index = 0
+
+var buffer = [0];
+
+for i in 1...2017 {
+	index = ((index + input) % buffer.count) + 1
+	buffer.insert(i, at: index)
+}
+
+print(buffer[buffer.index(of: 2017)! + 1])
+
+var last = 0
+
+index = 0
+
+for i in 1...50000000 {
+	index = ((index + input) % i) + 1
+	if index == 1 {
+		last = i
+	}
+}
+
+print(last)