Java Daily (May 21, 2012)

Date	2011/4/10
Name	BullsAndCows
Description	A number guessing game written in Java
Filename	BullsAndCowsJava.java
Content	Print the following message: Bulls and Cows ============== This is an ancient game with guessing numbers. Draw 4-digit random number. Print the following message: A secret number of 4-digit has been draw! Obtain a 4-digit number or "quit" from user by prompting following message repeatly: Please enter a 4-digit number (or type 'quit' to exit): If the input is "quit" show the following message (replace 0000 with the actual number being drawed The secret number is: 0000 Show the number of digit(s) that have correct position as bull and the number of digit(s) that appeared without exact position as cow. For instance: The random number is 1234 and the user input 1355. Exact position: "1", appeared without exact position: "3". The system should display the following message: 1 bull 1 cow If no digit found n the random number, the following should be shown instead: Neither a bull nor a cow! On the other hand, if the user guess the 4 digits correctly, the system should show the following message instead: 4 bulls! You are a genius! Ask the user to play again if 4 digits have been guessed correctly by showing the following message: Do you want to play a new game (Y/N)? Show the following message if user has chosen to quit the program: Thank you for playing Bulls and Cows!
Sample Input:
Sample Output:
Expected Test Command:	javac BullsAndCowsJava.java java BullsAndCowsJava

import java.util.Random;
import java.util.Scanner;
import java.util.regex.Pattern;
class BullsAndCowsJava{
	public static void main(String args[]){
		int i,j,bull=0,cow=0;
		int[] secretDigit,arr;
		Scanner scan=new Scanner(System.in);
		String msg, ans, playNextGame;
		secretDigit=new int[4];
		arr=new int[4];
		System.out.println("Bulls and Cows");
		System.out.println("==============");
		System.out.println("This is an ancient game with guessing numbers.");
		Random rand=new Random();
		Pattern regex=Pattern.compile("^\\d{4}$|^quit$");
		do{
			String secret="";
			playNextGame="";
			for(i=0;i<4;i++){
				secretDigit[i]=rand.nextInt(10);
				secret+=secretDigit[i];
			}
			System.out.println("A secret number of 4-digit has been draw!");
			do{
				do{
					System.out.print("Please enter a 4-digit number (or type 'quit' to exit):");
					ans=scan.nextLine().trim();
					System.out.println(ans);
				}while(!regex.matcher(ans).find());
				if(ans.equals("quit")){
					System.out.println("The secret number is: " + secret);
				}else{
					cow=0;
					bull=0;
					for(i=0;i<4;i++)
						try{
							arr[i]=Integer.parseInt(ans.substring(i,i+1));
							if(arr[i]==secretDigit[i]) bull++;
						}catch(NumberFormatException nfe){}						
					for(i=0;i<4;i++)
						for(j=0;j<4;j++)
							if(arr[j]==secretDigit[i]){
								cow++;
								arr[j]=-1;
								break;
							}
					cow-=bull;
					msg="";
					if(cow==0 && bull==0){
						msg="Neither a bull nor a cow!";
					}else{
						if(bull==4)
							msg="4 bulls! You are a genius!";
						else{
							if(cow==0){
								if(bull==1)
									msg="1 bull only.";
								else
									msg=bull + " bulls only.";
							}else if(bull==0){
								if(cow==1)
									msg="1 cow only.";
								else
									msg=cow + " cows only.";
							}else{
								if(bull==1)
									msg="1 bull and ";
								else
									msg=bull + " bulls and ";
								if(cow==1)
									msg+="1 cow.";
								else
									msg+=cow + " cows.";
							}
						}
					}
					System.out.println(msg);
				}
			}while(bull!=4 && !ans.equals("quit"));
			if(!ans.equals("quit")){
				do{
					System.out.print("Do you want to play a new game (Y/N)?");
					playNextGame=scan.nextLine().trim();
					System.out.println(playNextGame);
				}while(!playNextGame.toUpperCase().equals("Y") && !playNextGame.toUpperCase().equals("N"));
			}
		} while (playNextGame.toUpperCase().equals("Y") && !ans.equals("quit"));
		System.out.println("Thank you for playing Bulls and Cows!");
	}
}

Date	2011/4/9
Name	Add Two Numbers
Description	Add Two Numbers using Java
Filename	AddTwoNumJava.java
Content	Using the Standard input stream to enter different numbers or text Find two integers each time and, Display output the sum to the standard output stream. Repeat the all the steps until an EOF (End of File) signal received
Sample Input:	123 3.5 dsfasd 4 fdsafds 6
Sample Output:	126 0
Expected Test Command:	javac AddTwoNumRuby.java java AddTwoNumRuby < testdata.txt

import java.util.Scanner;
class AddTwoNumJava{
	public static void main(String args[]){
		Scanner in=new Scanner(System.in);
		long nCount=0,total=0;
		while(in.hasNext()){
			try{
				long temp=Long.parseLong(in.next());
				if(nCount++ %2==0){
					total=temp;
				}else{
					total+=temp;
					System.out.print(total+" ");
				}
			}catch(NumberFormatException n){
			}
		}
	}
}

Date	2011/4/8
Name	Hello Friend
Description	Ask user's name and echo greeting message to user using Java
Filename	HelloFriendJava.java
Content	Using the Standard output stream to prompt your:"Your name?" Then use the input stream to receive input from user. Display the greeting message "Hello, [user name]!" using standard output stream. Repeat all the steps until users press CTRL-Z (MS windows) or CTRL-D (Mac) or receive the EOF signal.
Sample Input:	Peter Pan
Sample Output:	Hello, Peter Pan!
Expected Test Command:	javac HelloFriendJava.java java HelloFriendJava < testdata.txt

import java.util.Scanner;
class HelloFriendJava{
	public static void main(String args[]){
		Scanner scan=new Scanner(System.in);
		System.out.print("Your Name?");
		while(scan.hasNext()){
			String name=scan.nextLine();
			System.out.println("Hello, "+name+"!");
			System.out.print("Your name?");
		}
	}
}

Date	2011/4/7
Name	Hello World
Description	Display greeting message to user using Java
Filename	HelloWorldJava.java
Content	Display the greeting message "Hello, World!" using standard output stream by Windows Scripting File using JScript
Sample Input:
Sample Output:	Hello, World!
Expected Test Command:	javac HelloWorldJava.java java HelloWorldJava

class HelloWorldJava{
	public static void main(String args[]){
		System.out.println("Hello, World!");
	}
}