Sync

Task/Josephus-problem/JavaScript/josephus-problem.js

@@ -0,0 +1,27 @@
+var Josephus = {
+  init: function(n) {
+    this.head = {};
+    var current = this.head;
+    for (var i = 0; i < n-1; i++) {
+      current.label = i+1;
+      current.next = {prev: current};
+      current = current.next;
+    }
+    current.label = n;
+    current.next = this.head;
+    this.head.prev = current;
+    return this;
+  },
+  kill: function(spacing) {
+    var current = this.head;
+    while (current.next !== current) {
+      for (var i = 0; i < spacing-1; i++) {
+        current = current.next;
+      }
+      current.prev.next = current.next;
+      current.next.prev = current.prev;
+      current = current.next;
+    }
+    return current.label;
+  }
+}