Add Java and C++ code for the section hash algorithm (#560)

codes/cpp/chapter_hashing/built_in_hash.cpp

@@ -0,0 +1,29 @@
+/**
+ * File: built_in_hash.cpp
+ * Created Time: 2023-06-21
+ * Author: Krahets (krahets@163.com)
+ */
+
+#include "../utils/common.hpp"
+
+/* Driver Code */
+int main() {
+    int num = 3;
+    size_t hashNum = hash<int>()(num);
+    cout << "整数 " << num << " 的哈希值为 " << hashNum << "\n";
+
+    bool bol = true;
+    size_t hashBol = hash<bool>()(bol);
+    cout << "布尔量 " << bol << " 的哈希值为 " << hashBol << "\n";
+
+    double dec = 3.14159;
+    size_t hashDec = hash<double>()(dec);
+    cout << "小数 " << dec << " 的哈希值为 " << hashDec << "\n";
+
+    string str = "Hello 算法";
+    size_t hashStr = hash<string>()(str);
+    cout << "字符串 " << str << " 的哈希值为 " << hashStr << "\n";
+
+    // 在 C++ 中，内置 std:hash() 仅提供基本数据类型的哈希值计算
+    // 数组、对象的哈希值计算需要自行实现
+}