Quick Select Search (#131)

* HeapSort algorithm

* Create QuickSelect.js

* Algorithm to reverse a string.

* Update ReverseString.js

* Update Heapsort.js

* Update QuickSelect.js

Co-authored-by: vinayak <itssvinayak@gmail.com>

Sorts/Heapsort.js

@@ -0,0 +1,48 @@
+let arrayLength = 0
+
+/* to create MAX  array */
+
+function heapRoot (input, i) {
+  const left = 2 * i + 1
+  const right = 2 * i + 2
+  let max = i
+
+  if (left < arrayLength && input[left] > input[max]) {
+    max = left
+  }
+
+  if (right < arrayLength && input[right] > input[max]) {
+    max = right
+  }
+
+  if (max !== i) {
+    swap(input, i, max)
+    heapRoot(input, max)
+  }
+}
+
+function swap (input, indexA, indexB) {
+  const temp = input[indexA]
+
+  input[indexA] = input[indexB]
+  input[indexB] = temp
+}
+
+function heapSort (input) {
+  arrayLength = input.length
+
+  for (let i = Math.floor(arrayLength / 2); i >= 0; i -= 1) {
+    heapRoot(input, i)
+  }
+
+  for (let i = input.length - 1; i > 0; i--) {
+    swap(input, 0, i)
+    arrayLength--
+
+    heapRoot(input, 0)
+  }
+}
+
+const arr = [3, 0, 2, 5, -1, 4, 1]
+heapSort(arr)
+console.log(arr)