package LeetCode;/**

* @Classname SubtreeOfAnotherTree

* @Description 判断树t是否为树s的子树

* @Date 19-5-30 上午10:57

* @Created by mao<tianmao818@qq.com>

*/

public class SubtreeOfAnotherTree {

public boolean isSubtree(TreeNode s, TreeNode t) {

boolean ans=false;

if (s!=null&&t!=null){

if(s.val==t.val){

ans=helper(s,t);

}

if(!ans){

ans=isSubtree(s.left,t);

}

if(!ans){

ans=isSubtree(s.right,t);

}

}

return ans;

}

public boolean helper(TreeNode s,TreeNode t){

if(t==null){

return true;

}

if (s==null){

return false;

}

if(s.val!=t.val){

return false;

}

return helper(s.left,t.left)&&helper(s.right,t.right);

}

}