Data commit

Task/Hailstone-sequence/Swift/hailstone-sequence.swift

@@ -0,0 +1,34 @@
+func hailstone(var n:Int) -> [Int] {
+
+    var arr = [n]
+
+    while n != 1 {
+
+        if n % 2 == 0 {
+            n /= 2
+        } else {
+            n = (3 * n) + 1
+        }
+
+        arr.append(n)
+    }
+
+    return arr
+}
+
+let n = hailstone(27)
+
+println("hailstone(27): \(n[0...3]) ... \(n[n.count-4...n.count-1]) for a count of \(n.count).")
+
+var longest = (n: 1, len: 1)
+
+for i in 1...100_000 {
+
+    let new = hailstone(i)
+
+    if new.count > longest.len {
+        longest = (i, new.count)
+    }
+}
+
+println("Longest sequence for numbers under 100,000 is with \(longest.n). Which has \(longest.len) items.")