kmp hashtable

CMakeLists.txt

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+cmake_minimum_required(VERSION 3.0)
+project(demo)
+
+set(CMAKE_CXX_STANDARD 11)
+
+add_executable(demo HashTable.cpp)

HashTable.cpp

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+//
+// Created by Administrator on 2023/7/19.
+//
+
+#include <cstdio>
+#include <memory>
+
+template <class T>
+struct node_base {
+    T data;
+    node_base* last = nullptr;
+    node_base* next = nullptr;
+};
+
+template <class T, class T1>
+class List {
+public:
+    List(size_t l = 10)
+    : node(new node_base<T>()), last(node), len(l), size(0) {
+        node_base<T>* for_old = nullptr;
+        node_base<T>* current = last;
+        for (int i = 0; i < len; ++i) {
+            if (i != 0)
+                current->last = for_old;
+            current->next = new node_base<T>();
+            for_old = current;
+            current = current->next;
+        }
+    }
+
+    void push_ele(T data) {
+        if (last->next != nullptr) {
+            last->data = data;
+            last = last->next;
+        } else {
+            node_base<T>* current = last;
+            for (int i = 0; i < len * 2; ++i) {
+                current->next = new node_base<T>();
+                current->next->last = current;
+                current = current->next;
+            }
+            len = len * 2;
+
+            last->data = data;
+            last = last->next;
+        }
+        ++size;
+    }
+
+    size_t find(T& data, std::function<T1(T*)>& fun) {
+        node_base<T>* header = node;
+        for (int i = 0; i < size; ++i) {
+            if (fun(&node->data) == fun(&data)) {
+
+                node = header;
+                return i;
+            }
+            node = node->next;
+            if (node == nullptr) {
+                node = header;
+                return -1;
+            }
+        }
+        return  -1;
+    }
+private:
+    node_base<T>* node;
+    node_base<T>* last;
+    size_t len;
+    size_t size;
+};
+
+template <class K, class V>
+struct pair {
+    K first;
+    V second;
+};
+
+template <class K, class V>
+class HashMap {
+public:
+    HashMap() : size(100) {
+        table = (List<pair<K, V>, K>**) malloc(sizeof( List<pair<K, V>, K>* ) * size);
+        for (int i = 0; i < size; ++i) {
+            table[i] = new List<pair<K, V>, K>();
+        }
+    }
+    virtual ~HashMap() {
+        delete table;
+    }
+public:
+    void insert(pair<K,V> ele) {
+        List<pair<K, V>, K>* list = table[buildHash(ele.first)];
+        list->push_ele(ele);
+    }
+
+    pair<K,V> find(K key) {
+        List<pair<K, V>, K>* list = table[buildHash(key)];
+        pair<K,V> pa = {key, ""};
+        std::function<V(pair<K,V>*)> fun = [&] (pair<K,V>* ele) {
+            if (ele != &pa) {
+                pa.second = ele->second;
+            }
+            return ele->first;
+        };
+
+        list->find(pa, fun);
+        return pa;
+    }
+private:
+    size_t buildHash(K key) {
+        std::hash<K> hash;
+        return hash(key) % size;
+    }
+
+private:
+    size_t size;
+    List<pair<K, V>, K>** table;
+};
+
+
+int main () {
+    HashMap<std::string, std::string> hashMap;
+    hashMap.insert({"one", "exe haha"});
+    auto item = hashMap.find("one");
+    printf("%s", item.second.c_str());
+}

kmp.cpp

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+//
+// Created by Administrator on 2023/7/18.
+//
+
+#include <string>
+
+// next 数组指针    patt 模式串
+void buildNext(int* next, const std::string& patt) {
+    int prefix; // 前缀
+    int suffix; // 后缀
+    for (prefix = 0, suffix = 0; suffix < patt.size(); ++suffix) {
+        // 前后缀不相同   不同 后缀一直后退
+        while (patt[prefix] != patt[suffix] && prefix != suffix && prefix > 0) {
+            prefix = next[prefix - 1];
+        }
+        // 前后缀相同  那全部向后移动 suffix 在for头里
+        if (patt[prefix] == patt[suffix] && prefix != suffix) {
+            ++prefix;
+        }
+        next[suffix] = prefix;
+    }
+}
+
+/**
+ * 查找 字符串 在文本中的 起始位置
+ * @param   str  待查文本
+ * @param   patt 模式串 查找的串
+ * @return  子串在主串中的起始位置
+ */
+size_t stringIndexOf(const std::string& str, const std::string& patt) {
+    if (str.empty() || patt.empty()) return -1;
+    int next[patt.size()];
+    buildNext(next, patt);
+
+    for (int str_i = 0, patt_i = 0; str_i < str.size(); ++str_i, ++patt_i) {
+        while (str[str_i] != patt[patt_i] && patt_i > 0) {
+            patt_i = next[patt_i - 1];
+        }
+        // patt_i +1 在for头内 不在 while 与 if 之间 这里的patt_i还没等待到自增 所以还是下标最大值
+        if (patt_i == patt.size() - 1) {
+            // str_1 是下标  patt.size() 是大小 差值1 故加1
+            return str_i - patt.size() + 1;
+        }
+    }
+
+    return -1;
+}
+
+int main() {
+    size_t index = stringIndexOf("aabaabaafa", "aabaaf");
+    printf("%zu\n", index);
+
+    std::string temp = "在这种困难的抉择下, 本人思来想去, 寝食难安.每个人都不得不面对这些问题. "
+                       "在面对这种问题时, 要想清楚, "
+                       "随机一段废话, 到底是一种怎么样的存在. "
+                       "随机一段废话似乎是一种巧合，但如果我们从一个更大的角度看待问题，"
+                       "这似乎是一种不可避免的事实. 要想清楚, 随机一段废话, 到底是一种怎么样的存在."
+                       "随机一段废话, 到底应该如何实现. 雷锋曾经提到过, "
+                       "自己活着，就是为了使别人过得更美好。这启发了我";
+
+    size_t index1 = stringIndexOf(temp, "随机一段废话");
+    printf("%zu\n", index1);
+    char text[] = {temp[index1], temp[index1+1], temp[index1+2]};
+    printf("%s\n", text);
+
+    size_t index2 = stringIndexOf("500201198807209975410101199712283432140201197412188071", "8807");
+    printf("%zu\n", index2);
+}

main.cpp

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+#include <iostream>