/**
5. Write a function,
string cat_dot(const string& s1, const string& s2),
that concatenates two strings with a dot in between.
For example, cat_dot("Niels", "Bohr") will return a
string containing Niels.Bohr.
*/

#include <iostream>
#include <string>
using namespace std;

string cat_dot(const string& s1, const string& s2, const string& s3)
{
    return s1+s2+s3;
}

int main() {
    string s1, s2, s3;

    cout << "\nEnter three strings: ";
    while(cin >> s1 >> s2 >> s3) {
        cout << cat_dot(s1,s2,s3);
        cout << "\nEnter two strings: ";
    }
}