[SOLVED] pls help...

hi everyone,
can someone help me w/ this
here is my code:
import java.io.*;
public class Num2
{
public static void main(String[]args)throws IOException
{
BufferedReader a=new BufferedReader(new InputStreamReader(System.in));
String comma;
int r1, c1, r2, c2;
int[][]cards;
cards=new int[4][4];
for(int r=0; r<4; r++)
{
for(int c=0; c<4; c++)
{
cards[r][c]=(int) (Math.random() * 8 + 1);
System.out.print(cards[r][c]);
}
System.out.print("\n");
}
for (int r=0; r<4; r++)
{
for (int c=0; c<4; c++)
{
System.out.print("*");
}
System.out.print("\n");
}
System.out.print("\nPlease insert the first card row and column seperated by a comma.");
r1=Integer.parseInt(a.readLine());
comma=a.readLine();
c1=Integer.parseInt(a.readLine());
System.out.print("\nPlease insert the second card row and column seperated by a comma.");
r2=Integer.parseInt(a.readLine());
comma=a.readLine();
c2=Integer.parseInt(a.readLine());
//reveal
for(int r=0; r<4; r++)
{
for (int c=0; c<4; c++)
{
if((r==r1)&&(c==c1))
{
System.out.print(cards[r][c]);
}
else if((r==r2)&&(c==c2))
{
System.out.print(cards[r][c]);
}
else
{
System.out.print("*");
}
System.out.println();
}
//match?
if (cards[r1][c1]==cards[r2][c2])
{
}
else
{
}
//this pushes the next board onto a blank screen
for (int b=0; b<=20; b++)
System.out.println();
}
}
}

my problem here is once i entered the row and columns,there is nothing happens..pls help,
here's the error...

---------- Capture Output ----------
> "C:\jdk1.3.0_02\bin\java.exe" Num2
5373
7563
5732
8555
****
****
****
****

Please insert the first card row and column seperated by a comma.1,2
java.lang.NumberFormatException:
at java.lang.Integer.parseInt(Integer.java:426)
at java.lang.Integer.parseInt(Integer.java:454)
at Num2.main(Num2.java:29)
Exception in thread "main"

and also how to hide the values of the cards,
i mean only the * can only be seen,
once the row and the column is inputted,
the values will only show,
pls help w/ my program

Can you post the code with code tags around it?

How are you inputting the first card row and column? Something like 2345,5678 ?
If so, the method you are using is "readLine()" which, as it's name says, reads the line of string, including the the comma. Therefore the comma is also being parsed as an int (which it can't) and this is what is giving the parseInt() method indigestion and eventually ending up in sending the "NumberFormatException" nastygram.

Luck,
CJSL

ok,
what if i erase the comma..
the comma=a.readLine?
is that solve the problem?

The way you are working is wrong, basically the way you are handling numbers are wrong.

Once your input is something like 1,2 you try to convert that string into a number using Integer wrapper class. So what should be the final value, it's 1,2 This is not a number anymore. That's why you get a NumberFormatException, simply it's an invalid number.

You didn't answer my question:

Quote:

---

How are you inputting the first card row and column? Something like 2345,5678 ?

---

• Are you inputting all at once, as one line: 1234,5678?
• Are you inputting first 1234 (enter), then the comma (enter) and last 5678 (enter) ?

Taking out the the following will not improve/hurt the program in any way because it's not used:

Code:

---

comma=a.readLine();

---

It would probably be better to read everything (1234,5678) as one string and then pull out what you want using the substring() method.

Luck,
CJSL

what if i erase the comma?
here is the code:

Code:

---

import java.io.*;
public class Num2
{
        public static void main(String[]args)throws IOException
        {
        BufferedReader a=new BufferedReader(new InputStreamReader(System.in));
       
        int r1, c1, r2, c2;
        int[][]cards;
        cards=new int[4][4];
        for(int r=0; r<4; r++)
        {
                for(int c=0; c<4; c++)
                {
                        cards[r][c]=(int) (Math.random() * 8);
                        System.out.print(cards[r][c]);
                }
                System.out.print("\n");
        }
            for (int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
          System.out.print("*");
        }
        System.out.print("\n");
        }
        System.out.print("\nPlease insert the first card row and column.");
        r1=Integer.parseInt(a.readLine());
       
        c1=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the second card row and column.");
        r2=Integer.parseInt(a.readLine());
       
        c2=Integer.parseInt(a.readLine());
        //reveal
        for(int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
        if((r==r1)&&(c==c1))
        {
                System.out.print(cards[r][c]);
        }
        else if((r==r2)&&(c==c2))
        {
                System.out.print(cards[r][c]);
        }
        else
        {
        System.out.print("*");
        }
        System.out.println();
        }
        //match?
            if (cards[r1][c1]==cards[r2][c2])
            {
            }
            else
            {
            }
            //this pushes the next board onto a blank screen
            for (int b=0; b<=20; b++)
        System.out.println();
        }       
}
}

---

it doesn't print any errors the problem is once the user enter their desired row and column,nothing happens..the number on the row and column they type didn't appear..waht's wrong?

Quote:

---

Originally Posted by beginner21

what if i erase the comma?
here is the code:

Code:

---

import java.io.*;
public class Num2
{
        public static void main(String[]args)throws IOException
        {
        BufferedReader a=new BufferedReader(new InputStreamReader(System.in));
       
        int r1, c1, r2, c2;
        int[][]cards;
        cards=new int[4][4];
        for(int r=0; r<4; r++)
        {
                for(int c=0; c<4; c++)
                {
                        cards[r][c]=(int) (Math.random() * 8);
                        System.out.print(cards[r][c]);
                }
                System.out.print("\n");
        }
            for (int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
          System.out.print("*");
        }
        System.out.print("\n");
        }
        System.out.print("\nPlease insert the first card row and column.");
        r1=Integer.parseInt(a.readLine());
       
        c1=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the second card row and column.");
        r2=Integer.parseInt(a.readLine());
       
        c2=Integer.parseInt(a.readLine());
        //reveal
        for(int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
        if((r==r1)&&(c==c1))
        {
                System.out.print(cards[r][c]);
        }
        else if((r==r2)&&(c==c2))
        {
                System.out.print(cards[r][c]);
        }
        else
        {
        System.out.print("*");
        }
        System.out.println();
        }
        //match?
            if (cards[r1][c1]==cards[r2][c2])
            {
            }
            else
            {
            }
            //this pushes the next board onto a blank screen
            for (int b=0; b<=20; b++)
        System.out.println();
        }       
}
}

---

it doesn't print any errors the problem is once the user enter their desired row and column,nothing happens..the number on the row and column they type didn't appear..waht's wrong?

---

Yes you cannot get any result until you enter few values. Look at the following in your cod.

Code:

---

        System.out.print("\nPlease insert the first card row and column " +
                "seperated by a comma.");
        r1 = Integer.parseInt(a.readLine());
        comma = a.readLine();
        c1 = Integer.parseInt(a.readLine());

---

What are you doing there? First of all build a well design/logic for your application. Then try to code it.

ok..
here is my modify code:

Code:

---

import java.io.*;
public class Num2
{
        public static void main(String[]args)throws IOException
        {
        BufferedReader a=new BufferedReader(new InputStreamReader(System.in));
       
        int r1, c1, r2, c2;
        int[][]cards;
        cards=new int[4][4];
        for(int r=0; r<4; r++)
        {
                for(int c=0; c<4; c++)
                {
                        cards[r][c]=(int) (Math.random() * 8);
                        System.out.print(cards[r][c]);
                }
                System.out.print("\n");
        }
            for (int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
          System.out.print("*");
        }
        System.out.print("\n");
        }
        System.out.print("\nPlease insert the first card row.");
        r1=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the first card column.");
        c1=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the second card row.");
        r2=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the first card column.");
        c2=Integer.parseInt(a.readLine());
        //reveal
        for(int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
        if((r==r1)&&(c==c1))
        {
                System.out.print(cards[r][c]);
        }
        else if((r==r2)&&(c==c2))
        {
                System.out.print(cards[r][c]);
        }
        else
        {
        System.out.print("*");
        }
        System.out.println();
        }
        //match?
            if (cards[r1][c1]==cards[r2][c2])
            {
            }
            else
            {
            }
            //this pushes the next board onto a blank screen
            for (int b=0; b<=20; b++)
        System.out.println();
        }       
}
}

---

the output the program is this:

Code:

---

1555
0672
2322
6011
****
****
****
****

Please insert the first card row.1

Please insert the first card column.2

Please insert the second card row.1

Please insert the second card column.2
*
*
*
*







*
*
7
*







*
*
*
*







*
*
*
*

---

it prints the exact place wherein the seven can be found,
but why it print in that way?

Because that's the way you work out. What's the way you want to print those values?

i want to print the value in this way?
****
**7*
****
****
when i try to erase the System.out.print("\n");
the output is this:
****







**7*







****







****

pls help

Are you sure that no additional spaces are printed in your code?

im not quite sure,
here is my new code:

Code:

---

import java.io.*;
public class Num2
{
        public static void main(String[]args)throws IOException
        {
        BufferedReader a=new BufferedReader(new InputStreamReader(System.in));
       
        int r1, c1, r2, c2;
        int[][]cards;
        cards=new int[4][4];
        for(int r=0; r<4; r++)
        {
                for(int c=0; c<4; c++)
                {
                        cards[r][c]=(int) (Math.random() * 8);
                        System.out.print(cards[r][c]);
                }
                System.out.print("\n");
        }
            for (int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
          System.out.print("*");
        }
        System.out.print("\n");
        }
        System.out.print("\nPlease insert the first card row: ");
        r1=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the first card column: ");
        c1=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the second card row: ");
        r2=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the first card column: ");
        c2=Integer.parseInt(a.readLine());
        //reveal
        for(int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
        if((r==r1)&&(c==c1))
        {
                System.out.print(cards[r][c]);
        }
        else if((r==r2)&&(c==c2))
        {
                System.out.print(cards[r][c]);
        }
        else
        {
        System.out.print("*");
        }
        }
        //match?
            if (cards[r1][c1]==cards[r2][c2])
            {
            }
            else
            {
            }
        }       
}
}

---

output:

Code:

---

0331
6102
6010
7132
****
****
****
****

Please insert the first card row: 1

Please insert the first card column: 2

Please insert the second card row: 3

Please insert the second card column: 3
******0********2

---

what should i do?

Can you tell me what the exact pattern you want to have, I'm not clear what you are talking about.

my problem here is i want the output to be print like this:
example:

Code:

---

Please insert the first card row: 1
Please insert the first card column: 2
Please insert the second card row: 3
Please insert the second card column: 3
****
**0*
****
***2

---

but i came up with this:

Code:

---

Please insert the first card row: 1
Please insert the first card column: 2
Please insert the second card row: 3
Please insert the second card column: 3
******0********2

---

what or where should i modify?

alright..
i print now the output that i wanted..
i have a question again..
i want to hide the values of the cards in my output.
here is my modified code:

Code:

---

import java.io.*;
public class Num2
{
        public static void main(String[]args)throws IOException
        {
        BufferedReader a=new BufferedReader(new InputStreamReader(System.in));
       
        int r1, c1, r2, c2;
        int[][]cards;
        cards=new int[4][4];
        for(int r=0; r<4; r++)
        {
                for(int c=0; c<4; c++)
                {
                        cards[r][c]=(int) (Math.random() * 8);
                        System.out.print(cards[r][c]);
                }
                System.out.print("\n");
        }
            for (int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
          System.out.print("*");
        }
        System.out.print("\n");
        }
        System.out.print("\nPlease insert the first card row: ");
        r1=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the first card column: ");
        c1=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the second card row: ");
        r2=Integer.parseInt(a.readLine());
        System.out.print("\nPlease insert the first card column: ");
        c2=Integer.parseInt(a.readLine());
        //reveal
        for(int r=0; r<4; r++)
            {
        for (int c=0; c<4; c++)
        {
        if((r==r1)&&(c==c1))
        {
                System.out.print(cards[r][c]);
        }
        else if((r==r2)&&(c==c2))
        {
                System.out.print(cards[r][c]);
        }
        else
        {
        System.out.print("*");
        }
        }
        //match?
            if (cards[r1][c1]==cards[r2][c2])
            {
            }
            else
            {
        System.out.println();
            }
        }       
}
}

---

the output is:
5264
7021
1741
1556
****
****
****
****
Please insert the first card row: 1
Please insert the first card column: 2
Please insert the second card row: 3
Please insert the second card column: 3
****
**2*
****
***6
[/code]
the values in my output are printed also..
before the 4x4 *;
what should i modify?

On the array it cause to print values.

Code:

---

        if((r==r1)&&(c==c1))
        {
                System.out.print(cards[r][c]);
        }

---

Rather printing the elements of the array, print the hiding character.

alright..
i hide now the values but why did the program stop after inputting some values?
i wanted that the program should continue until they match those hidden numbers..
i am working to have a memory matching game..
wherein if the value that they input is not match;
it prints the 4x4 * again;
and input again until the game completes,
is there any idea how to do it?

You have to do the same process inside a loop until the condition comes true.

will you post where i am exactly wrong?