The strings in C++ can be concatenated in two ways- one considering them string objects and second concatenating them C style strings.
#include <iostream>
using namespace std;
int main()
{
string s_1, s_2, fin;
cout << "Enter string";
getline (cin, s_1);
cout << "Enter string ";
getline (cin, s_2);
fin= s_1 + s_2;
cout << fin;
char str1[50], str2[50], fin[100];
cout << "Enter string";
cin.getline(str1, 50);
cout << "Enter string";
cin.getline(str2, 50);
strcat(str1, str2);
cout << "str1 = " << str1 << endl;
cout << "str2 = " << str2;
return 0;
}