Arrays

[Meena]

Q1>
public class lost {
public static void main (String [] args){
int [] array = new int[10];
int i=5;
array[i++]=++i+i++;
System.out.println(array[5]+" "+array[6]+" "+i);
}
}
When i tried to execute this code,i got answers to be as 14 0 8.
Could anybody answer how it could be 14 0 8.
because i think that array[i++]=++i+i++;for
int i = 5 is
array[5]=6+5=11.
array[6]=?
i=?

[paul wheaton]

When you init an int array, all values are initialized to zero.
i ends up being 8.
I have no idea where 14 is coming from.

[Thandapani Saravanan]

I think the value of the expression (when i equals 6)
++i + i++
(7) + (7)
is 14 and now the value of i is 8.
Here the mechanism of pre and post increment plays a role.

[Anonymous]

I think the i value is calculated as
int i=5;
array[i++]=++i+i++;
The following associativity & Order of precedence are applied to the above expression. Order of precedence is as listed below:
Symbol - Associativity - precedence
++ (post increment) - Left to Right
++ (pre increment) - right to left
+ - Left to Right
First i++ of the expression array[i++]is evaluated - here i value of the array is 5, and is post incremented to 6.
Next, i++ of the expression ++i+i++ is evaluated as i = 6 and is postinremented to 7.
Next, ++i of the expression ++i+i++ is evaluated as i = 8, so finally 8 + 6 = 14.

[Ganesh Narayanan]

The assignment Operator is an exception for arrays.
In this case i value in array[i++] gets incremented after the assignment operator i=6 now.
next ++i of the expression gets incremented (value is 7 ) now.
then i++ which is ( 7+7 )
The result is 14.
Think a bit ul find it logical

[Tracy Qi]

I am still confused here.
array[i++] = array[6]
But I think after this operation i is still 5. so how come i = 6?

[Bala Arul]

Hi Tracy,

Originally posted by Tracy Qi:
I am still confused here.
array[i++] = array[6]
But I think after this operation i is still 5. so how come i = 6?

[] is evaluted first then post-increment ++. That means,
array[i++] yealds array[5] and i = 6.
After this the evaluation of the expression on the right side of the equal sign is performed, and I hope that you are clear on that.
Bala Arul.

[This message has been edited by Bala Arul (edited May 03, 2001).]