Add update method to the heap

mgechev · mgechev · commit 424099235bc8 · 2014-12-06T19:44:57.000+02:00
diff --git a/src/data-structures/heap.js b/src/data-structures/heap.js
@@ -76,6 +76,18 @@
     return parent;
   };
 
+  /**
+   * Updates given node. This operation is useful
+   * in algorithms like Dijkstra, A* where we need
+   * to decrease/increase the value of givne node.
+   */
+  Heap.prototype.update = function (node) {
+    var idx = this._heap.indexOf(node);
+    if (idx >= 0) {
+      this.changeKey(idx, node);
+    }
+  };
+
   /**
    * Adds new element to the heap. Complexity O(log n).
    *
