LeetCode 100. Same Tree C语言

题目描述：

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

判断两个树是否一样

代码：

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     struct TreeNode *left;
 *     struct TreeNode *right;
 * };
 */
bool isSameTree(struct TreeNode* p, struct TreeNode* q) {
    if(!p && !q){
        return true;
    }
    if(!p && q){
        return false;
    }
    if(p && !q){
        return false;
    }
    else{
        if(q->val != p->val){
            return false;
        }else
            return isSameTree(p->left,q->left) && isSameTree(p->right,q->right);
    }
}