add c++ solution

add hello world example project

CPlusPlus/HelloWorld/main.cpp

@@ -0,0 +1,21 @@
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+	std::cout << "Hello" << " " << "World!" << std::endl;
+
+	int number = 10;
+
+	cout << number << endl;
+
+	cin >> number;
+	cout << "Input: " << number << endl;
+
+	char c;
+	cin >> c;
+	cout << "Input: " << c << endl;
+
+	return 0;
+}