problem with for loops

[nitya satheesh]

Hey!
I have a problem with the for loops in the following program.It's a little silly but it's really bugging me..

class twoDArray{
public static void main(String args[]){
int twoD[]=new int[4][5];
int i,j,k=0;
for(i=0;i<4;i++)//why no curly braces here
for(j=0;j<5;j++){
twoD[i][j]=k;
k++;
}
for(i=0;i<4;i++){
for(j=0;j<5;j++)
system.out.println(twoD[i][j]+" ");
system.out.println();
}
}
}

why doesn't the first for loop need any curly braces?

[fred rosenberger]

It's not just for loops. While loops are the same way.

According to the JLS, you can have exactly one 'thing' in the body of your loop. that thing can be (for example) a for-loop. Or an executable statement. Or a block of code surrounded by curly braces.

So, your first loop has one thing in it - a for-loop.

Now...just because you CAN leave those braces off doesn't mean you SHOULD. Pretty much everyone here is going to tell you to ALWAYS use them, whether they are strictly needed or not.

[Jj Hill]

System should be capitalized..

[Campbell Ritchie]

Welcome to the Ranch
You ought to indent that code, then you would be able to see the relationships between the different parts. You should also tell us (for both your questions) where the question comes from.

[Manu Somasekhar]

It is not a good practice to avoid braces like that.

[nitya satheesh]

Thanks a lot!!!
I have one more question about this code.
The output of this code is supposed to be :
0 1 2 3 4
5 6 7 8 9
10 11 12 13 14
15 16 17 18 19

but I get
0
1
2
3
4

5
6
7
8
9......

Why this difference?

I got this code form a book called Complete reference :Java.

[Seetharaman Venkatasamy]

you have to fiddle with System.out.print and System.out.println in some *rare* case nowadays...

[Manu Somasekhar]

Hi nitya ,
what about changing

system.out.println(twoD[i][j]+" "); 

to

system.out.print(twoD[i][j]+" ");