实通过字符串前缀从数组中找出搜索建议列表，写出你知道的所有实现方式，代码尽可能简洁，用C++实现-Go服务器开发

以下是几种用C++实现的方式，通过字符串前缀从数组中找出搜索建议列表：

#include <iostream>
#include <vector>
#include <string>

using namespace std;

// 方法一：线性搜索
vector<string> searchSuggestions1(const vector<string>& arr, const string& prefix) {
    vector<string> suggestions;
    for (const auto& word : arr) {
        if (word.substr(0, prefix.size()) == prefix) {
            suggestions.push_back(word);
        }
    }
    return suggestions;
}

// 方法二：二分搜索
vector<string> searchSuggestions2(const vector<string>& arr, const string& prefix) {
    vector<string> suggestions;
    
    auto lower = lower_bound(arr.begin(), arr.end(), prefix);
    for (auto it = lower; it != arr.end(); ++it) {
        if ((*it).substr(0, prefix.size()) != prefix) break;
        suggestions.push_back(*it);
    }
    
    return suggestions;
}

// 方法三：Trie树（字典树）
class TrieNode {
public:
    vector<TrieNode*> children;
};

void insertWord(TrieNode* root, const string& word) {
    TrieNode* node = root;
    for (char ch : word) {
        int index = ch - 'a';
        if (!node->children[index]) {
            node->children[index] = new TrieNode();
        }
        node = node->children[index];
    }
}

void findWords(TrieNode* node, string& currentPrefix, vector<string>& result, const string& prefix) {
    if (result.size() == 3 || !node)
        return;

    if (!currentPrefix.empty() && currentPrefix.find(prefix) == 0)
        result.push_back(currentPrefix);

    for (int i = 0; i < 26; ++i) {
        if (node->children[i]) {
            currentPrefix.push_back('a' + i);
            findWords(node->children[i], currentPrefix, result, prefix);
            currentPrefix.pop_back();
        }
    }
}

vector<string> searchSuggestions3(const vector<string>& arr, const string& prefix) {
    TrieNode* root = new TrieNode();

    for (const auto& word : arr)
        insertWord(root, word);

    vector<string> suggestions;
    string currentPrefix;
    findWords(root, currentPrefix, suggestions, prefix);

    return suggestions;
}

int main() {
    vector<string> arr = { "apple", "banana", "orange", "pear", "pineapple" };
    string prefix = "app";
    
    // 方法一：线性搜索
    vector<string> suggestions1 = searchSuggestions1(arr, prefix);
    
    // 方法二：二分搜索
    sort(arr.begin(), arr.end());
    vector<string> suggestions2 = searchSuggestions2(arr, prefix);
    
    // 方法三：Trie树
     vector<string> suggestions3 = searchSuggestions3(arr, prefix);

    cout << "方法一（线性搜索）的结果：" << endl;
  	for (const auto& suggestion : suggestions1) {
    		cout << suggestion << endl;
	}
	
	cout << "\n方法二（二分搜索）的结果：" << endl;
	for (const auto& suggestion : suggestions2) {
	    	cout << suggestion << endl;
	}
	
	cout << "\n方法三（Trie树）的结果：" << endl;
	for (const auto& suggestion : suggestions3) {
    		cout << suggestion << endl;
	}

	return 0;
}

以上代码展示了三种常见的实现方式：