From 13ecee85cfbb2256b5363598b0a54935e0eb7b79 Mon Sep 17 00:00:00 2001
From: satya-hash <sathyagangadhara@gmail.com>
Date: Fri, 30 Aug 2024 09:28:43 +0530
Subject: [PATCH] added reverse array using js

---
 .../01. Reverse an Array/Reverse_Array.js     | 46 +++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 02. Algorithms/01. Arrays/01. Reverse an Array/Reverse_Array.js

diff --git a/02. Algorithms/01. Arrays/01. Reverse an Array/Reverse_Array.js b/02. Algorithms/01. Arrays/01. Reverse an Array/Reverse_Array.js
new file mode 100644
index 00000000..26167ee0
--- /dev/null
+++ b/02. Algorithms/01. Arrays/01. Reverse an Array/Reverse_Array.js	
@@ -0,0 +1,46 @@
+// Method 1
+// time complexity: O(n)
+
+let arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+let res = [];
+for (let i = arr.length - 1; i >= 0; i--) {
+  res.push(arr[i]);
+}
+console.log(res);
+
+// Method 2
+// using two pointer approach
+// time complexity: O(n)
+
+arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+let left = 0,
+  right = arr.length - 1;
+while (left < right) {
+  let temp = arr[left];
+  arr[left] = arr[right];
+  arr[right] = temp;
+  left++;
+  right--;
+}
+console.log(arr);
+
+// Method 3
+// using in-built functions
+// time complexity: O(n)
+arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+arr.reverse();
+console.log(arr);
+
+// Method 4
+// using recursion
+// time complexity: O(n)
+arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+function reverseArray(arr, start, end) {
+  if (start >= end) return;
+  let temp = arr[start];
+  arr[start] = arr[end];
+  arr[end] = temp;
+  reverseArray(arr, start + 1, end - 1);
+}
+reverseArray(arr, 0, arr.length - 1);
+console.log(arr);