4.3

#define  _CRT_SECURE_NO_WARNINGS#include<iostream>#include<cstring>using namespace std;int main(){char first_name[20];char last_name[20];cout << "Enter your first name : ";cin.getline(first_name, 20);cout << "Enter your last name : ";cin >> last_name;strcat(last_name, ",");strcat(last_name, first_name);cout << "Here's the information in a single string: " << last_name << endl;return 0;}