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Joined: 2010-05-31
Points: 0

couldn't understand this code
In the following program, explain why the value "6" is printed twice in a row:
class PrePostDemo {
public static void main(String[] args){
int i = 3;
System.out.println(i); // "4"
System.out.println(i); // "5"
System.out.println(++i); // "6"
System.out.println(i++); // "6"
System.out.println(i); // "7"

The code System.out.println(++i); evaluates to 6, because the prefix version of ++ evaluates to the incremented value. The next line, System.out.println(i++); evaluates to the current value (6), then increments by one. So "7" doesn't get printed until the next line.

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Joined: 2010-08-16
Points: 0

The behavior of this operator depends on its position relativ to the operand.

When used before the operand, where it ihs known as the[b][i] pre-increment [/i][/b]operator, it increments the operand and evaluates to the incremented value of that operand. When used after the operand, where it is known as the[b][i] post-increment [/i][/b]operator, it increments its operand, but evaluates to the value of that operand before it was incremented.

For example, the following code sets both i and j to 2:

i = 1;
j = ++i;

But there lines set i to 2 and j to 1:

i = 1;
j = i++;

First Post :)

Message was edited by: elmu1