Learning - 2D array and method question.

[Russo]

Its getting through ok. but when it gets to that point it doesn't prompt for an input...which has got me. If i initialise another scanner class it goes through ok..but it probably shouldnt be the solution. code below.

  private void doit ()
    {

    // User input for value n
    Scanner console = new Scanner(System.in);
    System.out.print("Enter the number of tokens for each side:");
    int n = console.nextInt(); // read an Integer
     
    //Create the board
    Board();

    //Add n Stones for Black and White
    addStones(n, BLACK);
    addStones(n, WHITE);

    //Print the Board
    print();

    

Scanner console2 = new Scanner(System.in);
System.out.print("Enter board position (row col) : ");
String input = console2.nextLine();

System.out.println(input);
//get the input and split value

String[] token = input.split(" ");
int row = Integer.valueOf(token[0]);
int col = Integer.valueOf(token[1]);

if (valid(row,col)){

int rinc = 1; //to change
int cinc = 1; //to change

maxLength(row,col,rinc,cinc);


System.out.println(row + "," + col);
System.out.println(rinc + "," + cinc);
}
else{System.out.println("Invalid Board Position - Bye!");}


 

    //length(row,col,rinc,cinc) + length(row,col,-rinc,-cinc) - 1;



    }// End Method

[Hardo]

What is your maxLength() method doing? i think thats what its called.
might find solve in what that method is doing.

-Regards Hardo

[Russo]

Here is what the max length statement is doing now, it was there as blank code really before (testing other things). maxLength is to determine how many tokens of the same type are together in any direction.

int length = (maxLength(row,col,rinc,cinc) + maxLength(row,col,-rinc,-cinc) - 1);
                if (length == 5){
                    System.out.println("You have won!");
                }

pm me if you want to see the rest of the code. I have still had to initialise the second scanner class to get it working properly.

Also on another topic of this, something I havent learnt in class but how can you check the validility of a string? ie. I want to check if the user has entered the string correctly in format of:

XX XX

where X is an integer and there is a space in the middle?

Cheers,

Russo

[Singing Boyo]

I'll do my best to help, but all the code that follows is untested and error-prone...

For your scanner...

  private void doit ()
    {

    // User input for value n
    Scanner console = new Scanner(System.in);
    System.out.print("Enter the number of tokens for each side:");
    int n = console.nextInt(); // read an Integer
    console.nextLine();
    //skip a line... I think you are reading getting the end of the line after the int
    //the input line is really like 1000\n, so the nextInt() gets the 1000, but leaves the \n
    //so you get an empty string when it reads the nextline, because the newline (\n) is
    //next character
    //Create the board
    Board();

    //Add n Stones for Black and White
    addStones(n, BLACK);
    addStones(n, WHITE);

    //Print the Board
    print();

System.out.print("Enter board position (row col) : ");
String input = console.nextLine();

System.out.println(input);
//get the input and split value

String[] token = input.split(" ");
int row = Integer.valueOf(token[0]);
int col = Integer.valueOf(token[1]);

if (valid(row,col)){

int rinc = 1; //to change
int cinc = 1; //to change

maxLength(row,col,rinc,cinc);


System.out.println(row + "," + col);
System.out.println(rinc + "," + cinc);
}
else{System.out.println("Invalid Board Position - Bye!");}


 

    //length(row,col,rinc,cinc) + length(row,col,-rinc,-cinc) - 1;



    }// End Method

Hopefully that solves your problem.

As for validating a string... use String.matches(String regex) and the appropriate regex.

//for your example...
string.matches("\\d\\d \\d\\d");
//\d is a decimal-[0-9] and the space is your space, so it would be
//XX XX where X is a digit
//backslashes in regexes need to be escaped

[Russo]

Hi Singing Boyo,

That has done it! Thanks so much for your help. Thanks for the description in there to makes a lot of sense now! The regex also worked, I added a few more options with that to to allow a few valid inputs such as

XX XX
X X
XX X
X XX

I think i've got all user input under control now ;)