100. Same Tree (Easy)
https://leetcode.com/problems/same-tree/
Given two binary trees, write a function to check if they are the same or not.
Two binary trees are considered the same if they are structurally identical and the nodes have the same value.
Example 1:
Input: 1 1 / \ / \ 2 3 2 3 [1,2,3], [1,2,3] Output: true
Example 2:
Input: 1 1 / \ 2 2 [1,2], [1,null,2] Output: false
Example 3:
Input: 1 1 / \ / \ 2 1 1 2 [1,2,1], [1,1,2] Output: false
Solutions
class Solution {
public boolean isSameTree(TreeNode p, TreeNode q) {
if (p == null && q == null) {
return true;
}
if (p == null) {
return false;
}
if (q == null) {
return false;
}
if (p.val != q.val) {
return false;
}
boolean ans = isSameTree(p.left, q.left);
ans = ans && isSameTree(p.right, q.right);
return ans;
}
}