From 0b1d256d711955f7571c24f258087bdb7c7b9f05 Mon Sep 17 00:00:00 2001
From: Simone Spaccarotella <simone.spaccarotella@bbc.co.uk>
Date: Sun, 2 Jan 2022 06:37:59 +0000
Subject: [PATCH 1/2] Add generic Heap

---
 src/collections/Heap.ts | 96 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 96 insertions(+)
 create mode 100644 src/collections/Heap.ts

diff --git a/src/collections/Heap.ts b/src/collections/Heap.ts
new file mode 100644
index 0000000..5f9ef82
--- /dev/null
+++ b/src/collections/Heap.ts
@@ -0,0 +1,96 @@
+enum HeapType { MIN, MAX };
+
+abstract class Comparable<X> {
+  private value: X;
+
+  constructor(value: X) {
+    this.value = value;
+  }
+
+  public getValue(): X {
+    return this.value;
+  }
+
+  /**
+   * Return true if this object value is strictly greater than the specified item's value.
+   *
+   * @param item the "comparable" object.
+   */
+  public abstract gt(item: Comparable<X>): boolean;
+  /**
+   * Return true if this object value is strictly less than the specified item's value.
+   *
+   * @param item the "comparable" object.
+   */
+  public abstract lt(item: Comparable<X>): boolean;
+}
+
+class TheNumber extends Comparable<number> {
+  gt(item: Comparable<number>): boolean {
+    return this.getValue() > item.getValue();
+  }
+
+  lt(item: Comparable<number>): boolean {
+    return this.getValue() < item.getValue();
+  }
+}
+
+class Person extends Comparable<number> {
+  private name: string;
+
+  constructor(name: string, age: number = 0) {
+    super(age);
+    this.name = name;
+  }
+
+  public getName(): string {
+    return this.name;
+  }
+
+  public gt(item: Comparable<number>): boolean {
+    return this.getValue() > item.getValue();
+  }
+
+  public lt(item: Comparable<number>): boolean {
+    return this.getValue() < item.getValue();
+  }
+}
+
+class Heap<T extends Comparable<X>, X> {
+  private heap: Array<T>;
+  private heapType: HeapType;
+
+  constructor(heap: Array<T> = [], heapType: HeapType = HeapType.MAX) {
+    this.heap = heap;
+    this.heapType = heapType;
+  }
+
+  public get(): Comparable<X> {
+    if (this.heap.length === 0) return undefined;
+
+    let mu = this.heap[0];
+    for (let i = 1; i < this.heap.length; i++) {
+      if (this.heapType === HeapType.MAX && this.heap[i].gt(mu)) {
+        mu = this.heap[i];
+      }
+
+      if (this.heapType === HeapType.MIN && this.heap[i].lt(mu)) {
+        mu = this.heap[i];
+      }
+    }
+
+    return mu;
+  }
+}
+
+// const a = new TheNumber(3);
+// const b = new TheNumber(11);
+
+// const h: Heap<TheNumber, number> = new Heap([a, b], HeapType.MAX);
+// console.log(h.get());
+
+const a = new Person('Simone', 38);
+const b = new Person('Lalla', 40);
+
+const h: Heap<Person, number> = new Heap([a, b], HeapType.MAX);
+console.log((h.get() as Person).getName());

From 17225a9b4485bd3d7cb44b00e874053e87e41a3d Mon Sep 17 00:00:00 2001
From: Simone Spaccarotella <simone.spaccarotella@bbc.co.uk>
Date: Mon, 3 Jan 2022 19:40:03 +0000
Subject: [PATCH 2/2] Rename Heap in HeapArray

---
 src/collections/{Heap.ts => HeapArray.ts} | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
 rename src/collections/{Heap.ts => HeapArray.ts} (94%)

diff --git a/src/collections/Heap.ts b/src/collections/HeapArray.ts
similarity index 94%
rename from src/collections/Heap.ts
rename to src/collections/HeapArray.ts
index 5f9ef82..74dbe07 100644
--- a/src/collections/Heap.ts
+++ b/src/collections/HeapArray.ts
@@ -56,7 +56,7 @@ class Person extends Comparable<number> {
   }
 }
 
-class Heap<T extends Comparable<X>, X> {
+class HeapArray<T extends Comparable<X>, X> {
   private heap: Array<T>;
   private heapType: HeapType;
 
@@ -92,5 +92,5 @@ class Heap<T extends Comparable<X>, X> {
 const a = new Person('Simone', 38);
 const b = new Person('Lalla', 40);
 
-const h: Heap<Person, number> = new Heap([a, b], HeapType.MAX);
+const h: HeapArray<Person, number> = new HeapArray([a, b], HeapType.MAX);
 console.log((h.get() as Person).getName());