It is said to be a Facebook pen question. Let's see how to do it.

Design a variant class with the following features: variant v = string ("jams"); // assign a value to variant v2 = 18 using string; // assign a value to variant jam ["name"] = V using the numeric type; // assign a value to jam ["Age"] = v2 using the variant type; jam ["sex"] = string ("famale"); jam ["holobby"] = variant. list_elem (); // "array" type variant & holobby = jam ["holobby"]; holobby [0] = string ("basketball "); holobby [1] = string ("Baseball"); holobby [2] = string ("classic music"); const int magic_num1 = 0x101010; const int magic_num2 = 0x101011; holobby [3] = variant (magic_num1); // constructor... holobby [4] = magic_num2; jam ["Address"] ["state"] = string (""); // "recursion" multi-layer jam ["Address"] ["city"] = string (""); cout <jam ["Address"] ["city"] <"," <jam ["Age"] <Endl; // read

Implementation