100. Same Tree

####QUESTION: Given two binary trees, write a function to check if they are equal or not.

Two binary trees are considered equal if they are structurally identical and the nodes have the same value.

####EXPLANATION:

递归查看对应值

####SOLUTION:

public boolean isSameTree(TreeNode p, TreeNode q) {
    if(p==null&&q==null) return true;
    if(p!=null&&q!=null){
        if(p.val==q.val){
            return isSameTree(p.left,q.left)&isSameTree(p.right,q.right);
        }
    }
    return false;
}