how to make string concatenation in c+ code example

Example 1: c++ string concatenation

string first_name = "foo"
string last_name = "bar"
std::cout << first_name + " " + last_name << std::endl;

Example 2: Come concatenare stringhe in c++

char str1[] = "This ";
char str2[] = "is a string";
strcat (str1, str2); 
cout << str1 << endl;