Add C++, Python, Go code for chapter_hashing

codes/cpp/chapter_hashing/hash_map.cpp

@@ -0,0 +1,52 @@
+/*
+ * File: hash_map.cpp
+ * Created Time: 2022-12-14
+ * Author: msk397 (machangxinq@gmail.com)
+ */
+
+#include "../include/include.hpp"
+
+
+int main() {
+    /* 初始化哈希表 */
+    unordered_map<int, string> map;
+
+    /* 添加操作 */
+    // 在哈希表中添加键值对 (key, value)
+    map[12836] = "小哈";
+    map[15937] = "小啰";
+    map[16750] = "小算";
+    map[13276] = "小法";
+    map[10583] = "小鸭";
+    cout << "\n添加完成后，哈希表为\nKey -> Value" << endl;
+    PrintUtil::printHashMap(map);
+
+    /* 查询操作 */
+    // 向哈希表输入键 key ，得到值 value
+    string name = map[15937];
+    cout << "\n输入学号 15937 ，查询到姓名 " << name << endl;
+
+    /* 删除操作 */
+    // 在哈希表中删除键值对 (key, value)
+    map.erase(10583);
+    cout << "\n删除 10583 后，哈希表为\nKey -> Value" << endl;
+    PrintUtil::printHashMap(map);
+
+    /* 遍历哈希表 */
+    cout << "\n遍历键值对 Key->Value" << endl;
+    for (auto kv: map) {
+        cout << kv.first << " -> " << kv.second << endl;
+    }
+
+    cout << "\n单独遍历键 Key" << endl;
+    for (auto key: map) {
+        cout << key.first << endl;
+    }
+
+    cout << "\n单独遍历值 Value" << endl;
+    for (auto val: map) {
+        cout << val.second << endl;
+    }
+
+    return 0;
+}