判断走右子树是否对应相等

public class Solution {
    /**
     * 
     * @param p TreeNode类 
     * @param q TreeNode类 
     * @return bool布尔型
     */
    public boolean isSameTree (TreeNode p, TreeNode q) {
        // write code here
        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);
    }
}