fix: order of length check in remove()

Author: ashokdey

src/_DataStructures_/Heaps/MaxHeap/MaxHeap.test.js

@@ -47,4 +47,16 @@ describe('MaxHeap', () => {
     expect(mh.remove()).toEqual(1);
     expect(mh.getMax()).toEqual(null);
   });
+
+  it('Should return `null` on `remove() called on empty heap`', () => {
+    expect(mh.getMax()).toEqual(null);
+  });
+
+  it('Should create MaxHeap using collection : [2, 12, 0, 90]', () => {
+    const arr = [2, 12, 0, 90];
+    const mHBulk = new MaxHeap(arr);
+
+    expect(mHBulk.getMax()).toEqual(90);
+    // expect(mHBulk.()).toEqual(90);
+  });
 });

src/_DataStructures_/Heaps/MaxHeap/index.js

@@ -19,10 +19,13 @@ class MaxHeap {
     return this.heap[0] || null;
   }
 
-  // eslint-disable-next-line consistent-return
   remove() {
-    // return the element at the root
     const max = this.heap[0] || null;
+    // return the element at the root
+    if (this.heap.length === 1) {
+      this.heap.pop();
+    }
+
     if (this.heap.length > 1) {
       // move the leaf to the root
       this.heap[0] = this.heap[this.heap.length - 1];
@@ -31,11 +34,6 @@ class MaxHeap {
       // eslint-disable-next-line no-underscore-dangle
       this.__heapify(0);
     }
-
-    if (this.heap.length === 1) {
-      this.heap.pop();
-    }
-
     return max;
   }