Whats Wrong ??

Active member

Pls tell me whats wrong with this prog..this is not working..
this is the soln to 1st prob of Sec B in Specimen Paper 2010

import java.io.*;
class Prime
{
int arr[][],r,c;
Prime()throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Please Enter Number Of Rows : ");
r=Integer.parseInt(br.readLine());
System.out.println("Please Enter Number Of Columns : ");
c=Integer.parseInt(br.readLine());
}
int isPrime(int p)
{
for(int i=2;i<=p/2;i++)
if(p%i==0)
return 0;
return 1;
}
void fill()
{
int i,j,x=1,pos=1;
for(i=0;i<r;i++)
for(j=0;j<c;j++)
for(x=pos;;x++)
if(isPrime(x)==1)
{
pos=x;
arr[i][j]=x;
}
System.out.println("a");
}
void display()
{
for(int i=0;i<r;i++)
{
for(int j=0;j<c;j++)
System.out.println(arr[i][j]+" ");
System.out.println();
}
}
void main()throws IOException //if error is not thrown here,exception occurs.
{
Prime obj=new Prime(); //Object named obj is created.
obj.fill();
obj.display();
}
}

Active member

i am also struck in the same program..! Whats Wrong ?? Icon_sad

Active member

i just cant figure out why my prog is'nt working,, Sad

Active member

Done have removed 5-6 bugs from your prog..

Here is the correct version

Test output
Please Enter Number Of Rows :
5
Please Enter Number Of Columns :
5
2 3 5 7 11
13 17 19 23 29
31 37 41 43 47
53 59 61 67 71
73 79 83 89 97
//program

import java.io.*;
class mainp
{
public static void main(String args[])throws IOException //if error is not thrown here,exception occurs.
{
Prime obj=new Prime(); //Object named obj is created.
obj.fill();
obj.display();
}
}

class Prime
{
int arr[][],r,c;
Prime()throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Please Enter Number Of Rows : ");
r=Integer.parseInt(br.readLine());
System.out.println("Please Enter Number Of Columns : ");
c=Integer.parseInt(br.readLine());
arr=new int[r][c];
}
int isPrime(int p)
{
for(int i=2;i<=p/2;i++)
if(p%i==0)
return 0;
return 1;
}
void fill()
{
int i,j,x=2;
for(i=0;i<r;i++)
{
for(j=0;j<c;j++)
{
while(isPrime(x)!=1)
{x++;}
arr[i][j]=x;
x++;
}
}
}
void display()
{
for(int i=0;i<r;i++)
{
for(int j=0;j<c;j++)
{System.out.print(arr[i][j]+" ");}
System.out.println();
}
}
}

Active member

ALL IZZZZ WELLLLL

Subject: Re: Whats Wrong ?? Thu Mar 18, 2010 11:55 am

hey dude put the main method in the beginning else it wont work....... Whats Wrong ?? Icon_wink

Active member

thanks saif..
but are we allowed to make another class not mentioned in the question ??

Active member

@RC

thats exactly the question that I have planed to ask my comp teacher before exam.Unfortunately i don't have his mobile number or else i would have asked him by now

Active member

U don't need another class..!

Active member

no no no no..winrule..! can we just use any other class as an extra..? will there be any penalty for it.?

Active member

i know winrule we dont need it..just asking if its allowed..else it can be done this way--
import java.io.*;
public class Prime
{
int arr[][],r,c;
Prime()throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Please Enter Number Of Rows : ");
r=Integer.parseInt(br.readLine());
System.out.println("Please Enter Number Of Columns : ");
c=Integer.parseInt(br.readLine());
arr=new int[r][c];
}
public int isPrime(int p)
{
for(int i=2;i<=p/2;i++)
if(p%i==0)
return 0;
return 1;
}
public void fill()
{
int i,j,x=2;
for(i=0;i<r;i++)
for(j=0;j<c;j++)
{
while(isPrime(x)!=1)
{x++;}
arr[i][j]=x;
x++;
}
}
public void display()
{
for(int i=0;i<r;i++)
{
for(int j=0;j<c;j++)
System.out.printf("%2d ",arr[i][j]);
System.out.println();
}
}
public static void main(String args[])throws IOException //if error is not thrown here,exception occurs.
{
Prime obj=new Prime(); //Object named obj is created.
obj.fill();
obj.display();
}
}

Active member

yes RC.. that's what is expected..

@G-7, when they r not asking for it to be called from another class y do extra and give the examiner chance to cut marks?

Active member

ok thanks

Active member

Welcome..!