Merge pull request akgmage#1791 from akgmage/dev

add inorder traversal in go js and python

Author: akgmage

Trees/Binary Trees/inorder_traversal.go

@@ -0,0 +1,46 @@
+package main
+
+import "fmt"
+
+// TreeNode definition
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}
+
+func inorderTraversal(root *TreeNode) []int {
+	var result []int
+	var stack []*TreeNode
+	current := root
+
+	for current != nil || len(stack) > 0 {
+		// Traverse all the way to the leftmost node, pushing each node onto the stack
+		for current != nil {
+			stack = append(stack, current)
+			current = current.Left
+		}
+
+		// Pop the top node from the stack (current leftmost node)
+		current, stack = stack[len(stack)-1], stack[:len(stack)-1]
+
+		// Add the value of the current node to the result slice
+		result = append(result, current.Val)
+
+		// Move to the right subtree of the current node
+		current = current.Right
+	}
+
+	return result
+}
+
+func main() {
+	// Create a sample binary tree
+	root := &TreeNode{Val: 1, Right: &TreeNode{Val: 2, Left: &TreeNode{Val: 3}}}
+
+	// Perform in-order traversal
+	result := inorderTraversal(root)
+
+	// Print the result
+	fmt.Println(result) // Output: [1 3 2]
+}

Trees/Binary Trees/inorder_traversal.js

@@ -0,0 +1,43 @@
+class TreeNode {
+  constructor(val) {
+    this.val = val;
+    this.left = this.right = null;
+  }
+}
+
+class Solution {
+  inorderTraversal(root) {
+    const result = [];
+    const stack = [];
+    let current = root;
+
+    while (current || stack.length > 0) {
+      // Traverse all the way to the leftmost node, pushing each node onto the stack
+      while (current) {
+        stack.push(current);
+        current = current.left;
+      }
+
+      // Pop the top node from the stack (current leftmost node)
+      current = stack.pop();
+
+      // Add the value of the current node to the result array
+      result.push(current.val);
+
+      // Move to the right subtree of the current node
+      current = current.right;
+    }
+
+    return result;
+  }
+}
+
+// Example usage
+const root = new TreeNode(1);
+root.right = new TreeNode(2);
+root.right.left = new TreeNode(3);
+
+const solution = new Solution();
+const result = solution.inorderTraversal(root);
+
+console.log(result); // Output: [1, 3, 2]

Trees/Binary Trees/inorder_traversal.py

@@ -0,0 +1,37 @@
+class TreeNode:
+    def __init__(self, val):
+        self.val = val
+        self.left = self.right = None
+
+class Solution:
+    def inorderTraversal(self, root):
+        result = []
+        stack = []
+        current = root
+
+        while current or stack:
+            # Traverse all the way to the leftmost node, pushing each node onto the stack
+            while current:
+                stack.append(current)
+                current = current.left
+
+            # Pop the top node from the stack (current leftmost node)
+            current = stack.pop()
+
+            # Add the value of the current node to the result list
+            result.append(current.val)
+
+            # Move to the right subtree of the current node
+            current = current.right
+
+        return result
+
+# Example usage
+root = TreeNode(1)
+root.right = TreeNode(2)
+root.right.left = TreeNode(3)
+
+solution = Solution()
+result = solution.inorderTraversal(root)
+
+print(result)  # Output: [1, 3, 2]