cuckoo hash代码

以下是一个简单的C++实现Cuckoo Hash的示例代码：

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

const int TABLE_SIZE = 11;
const int MAX_RETRIES = 500;

class CuckooHash {
private:
    vector<int> table1;
    vector<int> table2;
public:
    CuckooHash() {
        table1.resize(TABLE_SIZE);
        table2.resize(TABLE_SIZE);
    }

    int hash1(int key) {
        return key % TABLE_SIZE;
    }

    int hash2(int key) {
        return (key / TABLE_SIZE) % TABLE_SIZE;
    }

    void insert(int key) {
        int count = 0;
        while (count < MAX_RETRIES) {
            int index1 = hash1(key);
            int index2 = hash2(key);
            if (table1[index1] == key || table2[index2] == key) {
                cout << key << " already exists." << endl;
                return;
            }
            if (table1[index1] == 0) {
                table1[index1] = key;
                return;
            } else if (table2[index2] == 0) {
                table2[index2] = key;
                return;
            } else {
                int evictedKey = table1[index1];
                table1[index1] = key;
                key = table2[index2];
                table2[index2] = evictedKey;
                count++;
            }
        }
        cout << "Insertion failed." << endl;
    }

    void remove(int key) {
        int index1 = hash1(key);
        int index2 = hash2(key);
        if (table1[index1] == key) {
            table1[index1] = 0;
        } else if (table2[index2] == key) {
            table2[index2] = 0;
        } else {
            cout << key << " does not exist." << endl;
        }
    }

    bool search(int key) {
        int index1 = hash1(key);
        int index2 = hash2(key);
        return table1[index1] == key || table2[index2] == key;
    }
};

int main() {
    CuckooHash hash;
    hash.insert(10);
    hash.insert(22);
    hash.insert(37);
    hash.insert(40);
    hash.insert(50);
    hash.insert(60);
    hash.remove(22);
    hash.remove(40);
    hash.insert(70);
    hash.insert(80);
    cout << "Search for 10: " << (hash.search(10) ? "Found" : "Not Found") << endl;
    cout << "Search for 37: " << (hash.search(37) ? "Found" : "Not Found") << endl;
    cout << "Search for 50: " << (hash.search(50) ? "Found" : "Not Found") << endl;
    cout << "Search for 80: " << (hash.search(80) ? "Found" : "Not Found") << endl;
    cout << "Search for 90: " << (hash.search(90) ? "Found" : "Not Found") << endl;
    return 0;
}

代码中使用了两个哈希表作为Cuckoo Hash的基础数据结构，其中使用了两个不同的哈希函数来计算每个键的两个哈希值。在插入键时，如果一个键已经存在于两个哈希表中的任何一个中，则插入操作失败。如果两个哈希表中有一个空闲位置，则将键插入其中一个哈希表中。如果两个哈希表中都没有空闲位置，则使用Cuckoo Hash算法将其中一个哈希表中的键替换为新插入的键，同时将被替换的键移动到另一个哈希表中。在删除键时，如果一个键存在于哈希表中，则将其从哈希表中删除。在搜索键时，如果一个键存在于两个哈希表中的任何一个中，则返回true，否则返回false。