LeetCode/100_Same_Tree at master · KnowledgeCenterYoutube/LeetCode · GitHub

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Leetcode 100: Same Tree
Detailed video explanation of Recursive and Iterative Approach: https://youtu.be/5qj18l76xy4

C++:
====
Recursive:
----------
bool isSameTree(TreeNode* p, TreeNode* q) {
    if(!p && !q) return true;
    if(!p || !q) return false;
    if(p->val != q->val) return false;

    return isSameTree(p->left, q->left) && isSameTree(p->right, q->right);
}

Iterative:
----------
class Solution {
    bool areEqual(TreeNode* p, TreeNode* q){
        if(!p && !q) return true;
        if(!p || !q) return false;
        if(p->val != q->val) return false;
        return true;
    }
public:
    bool isSameTree(TreeNode* p, TreeNode* q) {
        if(!areEqual(p, q)) return false;
        queue<TreeNode*> Q1, Q2;
        Q1.push(p);
        Q2.push(q);
        while(!Q1.empty()){
            TreeNode* n1 = Q1.front();
            Q1.pop();
            TreeNode* n2 = Q2.front();
            Q2.pop();

            if(!areEqual(n1, n2)) return false;
            if(n1){
                if(!areEqual(n1->left, n2->left)) return false;
                if(n1->left){
                    Q1.push(n1->left);
                    Q2.push(n2->left);
                }
                if(!areEqual(n1->right, n2->right)) return false;
                if(n1->right){
                    Q1.push(n1->right);
                    Q2.push(n2->right);
                }
            }
        }
        return true;
    }


Java:
=====
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);
}


Python3:
========
def isSameTree(self, p: TreeNode, q: TreeNode) -> bool:
    if p == None and q == None: return True
    if p == None or q == None: return False
    if p.val != q.val: return False

    return self.isSameTree(p.left, q.left) and self.isSameTree(p.right, q.right)