Implement day 17, in swift.

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)