SpringBoot电商项目进阶Day6

SpringBoot电商项目进阶

对该项目一些代码进行了优化，对于重复的代码进行了抽离等等

Nginx

学习了Nginx的使用场景，并且学习了Nginx的优点

1.性能好，支持高并发

2.应用广泛

3.社区活跃度高，有问题有地方去找解决方法

4.高可用，可以热部署，服务非常稳定

5.用法简单，容易上手

字典树Trie

leetcode677

import java.util.TreeMap;

class MapSum {
    private class Node {
        public int value;
        public TreeMap<Character,Node> next;

        public Node(int value) {
            this.value = value;
            next = new TreeMap<>();
        }

        public Node() {
            this(0);
        }
    }

    private Node root;
    public MapSum() {
        root = new Node();
    }

    public void insert(String word, int val) {
        Node cur = root;
        for (int i = 0; i < word.length(); i++) {
            char c = word.charAt(i);
            if (cur.next.get(c) == null) {
                cur.next.put(c, new Node());
            }
            cur = cur.next.get(c);
        }
        cur.value = val;
    }

    public int sum(String prefix) {
        Node cur = root;
        for (int i = 0; i < prefix.length(); i++) {
            char c = prefix.charAt(i);
            if (cur.next.get(c) == null) {
                return 0;
            }
            cur = cur.next.get(c);
        }
        return sum(cur);
    }

    private int sum(Node node) {
//        if (node.next.size() == 0) {
//            return node.value;
//        }
        int res = node.value;
        for (char c : node.next.keySet()) {
            res += sum(node.next.get(c));
        }
        return res;
    }
}

/**
 * Your MapSum object will be instantiated and called as such:
 * MapSum obj = new MapSum();
 * obj.insert(key,val);
 * int param_2 = obj.sum(prefix);
 */

leetcode211

import java.util.TreeMap;

class WordDictionary {
    private class Node {
        public boolean isWord;
        public TreeMap<Character,Node> next;

        public Node(boolean isWord) {
            this.isWord = isWord;
            next = new TreeMap<>();
        }

        public Node() {
            this(false);
        }
    }

    private Node root;
    public WordDictionary() {
        root = new Node();
    }

    public void addWord(String word) {
        Node cur = root;
        for (int i = 0; i < word.length(); i++) {
            char c = word.charAt(i);
            if (cur.next.get(c) == null) {
                cur.next.put(c, new Node());
            }
            cur = cur.next.get(c);
        }
        cur.isWord = true;
    }

    public boolean search(String word) {
        return match(root, word, 0);
    }

    private boolean match(Node node, String word, int index) {
        if (index == word.length())
            return node.isWord;
        char c = word.charAt(index);
        if (c != '.') {
            if (node.next.get(c) == null) {
                return false;
            }
            return match(node.next.get(c), word, index + 1);
        } else {
            for (char nextChar : node.next.keySet()) {
                if (match(node.next.get(nextChar), word, index + 1)) {
                    return true;
                }
            }
            return false;
        }
    }
}

/**
 * Your WordDictionary object will be instantiated and called as such:
 * WordDictionary obj = new WordDictionary();
 * obj.addWord(word);
 * boolean param_2 = obj.search(word);
 */