算法--字典树

https:// www.bilibili.com/video/av53794167?from=search&seid=6694082725022421560 

import java.util.Scanner;
class TreeNode{
    final static int MAX_SIZE = 26;
    char data;
    boolean isEnd = false ;
    TreeNode [] childs = new TreeNode[MAX_SIZE];
}
public class TireTree{                                                    //字典树的构建 a~z 转化为 0~25 输入一个值构建一次
    public static void createTree(TreeNode node , String str) {
        char d [] = str.toCharArray();
        for(int i = 0 ; i < d.length ; i++) {
            int loc = d[i] - 'a';
            if(node.childs[loc]==null) {
                node.childs[loc] = new TreeNode();                      //没有存在则创建 存在继续
                node.childs[loc].data = d[i];
            }
            node = node.childs[loc];
        }
    }
    public static boolean find(TreeNode node,String str) {              //没有找到 直接就返回false
        char a [] = str.toCharArray();
        for(int i = 0 ; i < a.length ; i++) {
            int loc = a[i] - 'a';
            if(node.childs[loc]==null) {
                return false;
            }
            node = node.childs[loc];
        }
        return true;
    } 
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        TreeNode root = new TreeNode();
        while(sc.hasNext()) {
            String s = sc.nextLine();
            createTree(root, s);
            System.out.println(find(root,s));
        }
    }
}

create的方法 省略其他