same binary tree

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:
    def isSameTree(self, p: TreeNode | None, q: TreeNode | None) -> bool:
        if p is None and q is None:
            return True
 
        if p is None or q is None:
            return False
        
        if p.val != q.val:
            return False
 
        return self.isSameTree(p.left, q.left) and self.isSameTree(p.right, q.right)

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    public boolean isSameTree(TreeNode p, TreeNode q) {
        if (p == null && q == null) {
            return true;
        }
 
        if (p == null || q == null) {
            return false;
        }
 
        if (p.val != q.val) {
            return false;
        }
 
        return isSameTree(p.left, q.left) && isSameTree(p.right, q.right);
    }
}

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:
    def isSameTree(self, p: TreeNode | None, q: TreeNode | None) -> bool:
        stack = [(p, q)]
 
        while stack:
            a, b = stack.pop()
 
            if not a and not b:
                continue
 
            if not a or not b or a.val != b.val:
                return False
 
            stack.append((a.left, b.left))
            stack.append((a.right, b.right))
 
        return True

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    public boolean isSameTree(TreeNode p, TreeNode q) {
        Deque<TreeNode[]> stack = new ArrayDeque<>();
        stack.push(new TreeNode[]{p, q});
 
        while (!stack.isEmpty()) {
            TreeNode[] pairs = stack.pop();
            TreeNode a = pairs[0], b = pairs[1];
 
            if (a == null && b == null) {
                continue;
            }
 
            if (a == null || b ==null || a.val != b.val) {
                return false;
            }
 
            stack.push(new TreeNode[] {a.left, b.left});
            stack.push(new TreeNode[]{a.right, b.right});
 
        }
 
        return true;
    }
}