From 0015de616b60f4a915752fe6f8fb5d38fd44de28 Mon Sep 17 00:00:00 2001
From: Ranganathan S V <rangu230801@gmail.com>
Date: Mon, 27 Feb 2023 11:01:18 +0530
Subject: [PATCH 1/2] fix: fixed error in DepthFirstSearch algorithm and test:
 added tests for DepthFirstSearch algorithm.

---
 Trees/DepthFirstSearch.js           | 35 ++++++++++------------
 Trees/test/DepthFirstSearch.test.js | 46 +++++++++++++++++++++++++++++
 2 files changed, 62 insertions(+), 19 deletions(-)
 create mode 100644 Trees/test/DepthFirstSearch.test.js

diff --git a/Trees/DepthFirstSearch.js b/Trees/DepthFirstSearch.js
index 0833d9d1de..b436704368 100644
--- a/Trees/DepthFirstSearch.js
+++ b/Trees/DepthFirstSearch.js
@@ -4,35 +4,32 @@
  * DFS Algorithm for traversing or searching graph data structures.
 */
 
-function traverseDFS (root) {
-  const stack = [root]
+// traverses a give tree from specified root
+function traverseDFS (tree, root) {
+  const stack = []
   const res = []
-
+  stack.push(searchDFS(tree, root))
+  // if root is not present in the tree, returning empty array
+  if (!stack[0]) return res
   while (stack.length) {
     const curr = stack.pop()
-    res.push(curr.key)
-
-    if (curr.right) {
-      stack.push(curr.right)
-    }
-
+    res.push(curr.value)
     if (curr.left) {
-      stack.push(curr.left)
+      stack.push(tree[curr.left])
+    }
+    if (curr.right) {
+      stack.push(tree[curr.right])
     }
   }
-
   return res.reverse()
 }
 
 function searchDFS (tree, value) {
   const stack = []
-
   stack.push(tree[0])
-
   while (stack.length !== 0) {
     for (let i = 0; i < stack.length; i++) {
       const node = stack.pop()
-
       if (node.value === value) {
         return node
       }
@@ -59,11 +56,10 @@ const tree = [
   { value: 10, left: null, right: null },
   { value: 1, left: null, right: null }
 ]
-
-searchDFS(tree, 9)
-searchDFS(tree, 10)
-
-traverseDFS(6)
+searchDFS(tree, 9) // { value: 9, left: 7, right: 8 }
+searchDFS(tree, 200) // null
+traverseDFS(tree, 6) // [ 1, 2, 3, 4, 5, 8, 10, 9, 7, 6 ]
+traverseDFS(tree, 200) // []
 
 //            6
 //           / \
@@ -74,3 +70,4 @@ traverseDFS(6)
 //      2       8   10
 //     /
 //    1
+export { searchDFS, traverseDFS }
diff --git a/Trees/test/DepthFirstSearch.test.js b/Trees/test/DepthFirstSearch.test.js
new file mode 100644
index 0000000000..6c76fbb3d6
--- /dev/null
+++ b/Trees/test/DepthFirstSearch.test.js
@@ -0,0 +1,46 @@
+import { searchDFS, traverseDFS } from '../DepthFirstSearch'
+
+describe('Depth First Tree Traversal', () => {
+  const tree = [
+    { value: 6, left: 1, right: 2 },
+    { value: 5, left: 3, right: 4 },
+    { value: 7, left: null, right: 5 },
+    { value: 3, left: 6, right: null },
+    { value: 4, left: null, right: null },
+    { value: 9, left: 7, right: 8 },
+    { value: 2, left: 9, right: null },
+    { value: 8, left: null, right: null },
+    { value: 10, left: null, right: null },
+    { value: 1, left: null, right: null }
+  ]
+
+  //            6
+  //           / \
+  //          5   7
+  //         / \   \
+  //        3   4   9
+  //       /       / \
+  //      2       8   10
+  //     /
+  //    1
+
+  it('should be null if given value is not present in the tree - DF Search', () => {
+    const res = searchDFS(tree, 200)
+    expect(res).toStrictEqual(null)
+  })
+
+  it('should return the node if given value is present in the tree - DF Search', () => {
+    const res = searchDFS(tree, 9)
+    expect(res).toStrictEqual({ value: 9, left: 7, right: 8 })
+  })
+
+  it('should return empty array if given root is not present in the tree - DF Traversal', () => {
+    const traversal = traverseDFS(tree, 200)
+    expect(traversal).toStrictEqual([])
+  })
+
+  it('should return DFT array of given tree from specified root if given root is present in the tree - DF Traversal', () => {
+    const traversal = traverseDFS(tree, 6)
+    expect(traversal).toStrictEqual([1, 2, 3, 4, 5, 8, 10, 9, 7, 6])
+  })
+})

From 7cd3870b11d33bc7a731180fdceb79190c052e2d Mon Sep 17 00:00:00 2001
From: Ranganathan S V <rangu230801@gmail.com>
Date: Tue, 28 Feb 2023 16:14:16 +0530
Subject: [PATCH 2/2] changed traverseDFS function parameters in
 DepthFirstSearch.js file

---
 Trees/DepthFirstSearch.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/Trees/DepthFirstSearch.js b/Trees/DepthFirstSearch.js
index b436704368..4c0c43db41 100644
--- a/Trees/DepthFirstSearch.js
+++ b/Trees/DepthFirstSearch.js
@@ -4,11 +4,11 @@
  * DFS Algorithm for traversing or searching graph data structures.
 */
 
-// traverses a give tree from specified root
-function traverseDFS (tree, root) {
+// traverses a give tree from specified root's value
+function traverseDFS (tree, rootValue) {
   const stack = []
   const res = []
-  stack.push(searchDFS(tree, root))
+  stack.push(searchDFS(tree, rootValue))
   // if root is not present in the tree, returning empty array
   if (!stack[0]) return res
   while (stack.length) {