Stack on singly linked list

tshemsedinov · tshemsedinov · commit c25f3f3268c5 · 2018-02-11T20:59:34.000+02:00
diff --git a/JavaScript/1-stack.js b/JavaScript/1-stack.js
@@ -0,0 +1,34 @@
+'use strict';
+
+class Stack {
+  constructor() {
+    this.last = null;
+  }
+  push(item) {
+    const prev = this.last;
+    const element = { prev, item };
+    this.last = element;
+  }
+  pop() {
+    const element = this.last;
+    if (!element) return null;
+    this.last = element.prev;
+    return element.item;
+  }
+}
+
+// Usage
+
+const obj1 = { name: 'first' };
+const obj2 = { name: 'second' };
+const obj3 = { name: 'third' };
+
+const list = new Stack();
+list.push(obj1);
+list.push(obj2);
+list.push(obj3);
+
+console.dir(list.pop());
+console.dir(list.pop());
+console.dir(list.pop());
+console.dir(list.pop());
