数据结构之二叉树查询

二叉树之查询

二叉树的查询是建立遍历的基础上更进一步的对比查询，下面分别从前序、中序、后续三种方法中查询对应的节点。

前序查找

    /*** 前序查询*/public Person preSelectById(Integer id) {Person person = null;if (this.data.getId().equals(id)) {person = this.data;}if (Objects.isNull(person) && Objects.nonNull(this.left)) {person = this.left.preSelectById(id);}if (Objects.isNull(person) && Objects.nonNull(this.right)) {person = this.right.preSelectById(id);}return person;}

中序查找

    /*** 中序查询*/public Person midSelectById(Integer id) {Person person = null;if (Objects.isNull(person) && Objects.nonNull(this.left)) {person = this.left.preSelectById(id);}if (this.data.getId().equals(id)) {person = this.data;}if (Objects.isNull(person) && Objects.nonNull(this.right)) {person = this.right.preSelectById(id);}return person;}

后序查找

    /*** 后序查询*/public Person postSelectById(Integer id) {Person person = null;if (Objects.isNull(person) && Objects.nonNull(this.left)) {person = this.left.preSelectById(id);}if (Objects.isNull(person) && Objects.nonNull(this.right)) {person = this.right.preSelectById(id);}if (this.data.getId().equals(id)) {person = this.data;}return person;}

源码与测试案例

gitee地址