C :

#include<stdio.h>
#include<string.h>
int main()
{
	char x[100];
	while(gets(x)!=0)
		printf("Hello %s.\n",x);
	return 0;
}

C++ :

#include<iostream>
using namespace std;

int main()
{
	char s[20];
	cin.getline(s,20);
	cout<<"Hello "<<s<<".";
	return 0;
}

Java :

import java.util.Scanner;


public class Main {

	
	
	public static void main(String[] args) {
		
		Scanner scan=new Scanner(System.in);
		while(scan.hasNext())
		{
			String s=scan.nextLine();
			System.out.print("Hello "+s+".");
		}
		

	}

}