Create heap.js

Author: jackietian

basics/heap.js

@@ -0,0 +1,50 @@
+class PriorityQueue {
+    constructor() {
+        this.items = [];
+    }
+
+    enqueue(item) {
+        for(let i = 0; i < this.items.length; i++) {
+            if(this.items[i] < item) {
+                this.items.splice(i, 0, item);
+                return;
+            }
+        }
+
+        this.items.push(item);
+    }
+
+    dequeue() {
+        return this.items.pop();
+    }
+
+    peek() {
+        console.log(this.items);
+    }
+
+    print() {
+        console.log(this.items);
+    }
+
+    length() {
+        return this.items.length;
+    }
+}
+
+const findKthLargestNum = (nums,k) => {
+    const queue = new PriorityQueue();
+    nums.forEach(num => {
+        if(queue.length() < k) {
+            queue.enqueue(num);
+            return;
+        }
+
+        queue.enqueue(num);
+        queue.dequeue();
+    });
+    queue.peek();
+    return queue.dequeue();
+}
+
+const nums = [6,3,7,4];
+findKthLargestNum(nums,2);