Related to Looping..

[Anish Nagraj]

How does this work... Plz explain...

 
public class FlowControl {

    static boolean b;
    static int i;
    
    public static void main(String[] args) {
        int j = 0;
do 
            for (int i = 0; i++ < 2  :wink:    
    System.out.print(i);
while (j++ < 2);
    }
}

i get the result as 121212
no way i am able to trace the flow... plz explain me abt this ...

[ADDED Code Tags to make code readable. Mark]
[ March 03, 2006: Message edited by: Mark Spritzler ]

[Mark Spritzler]

OK, you have your do-while loop that only checks after it runs the for loop.

(A) The for loop counts, since the post incrementer is on the boolean expression,
(B)the check is first i = 0 and it is less than 2,
(C) now increment it to 1.
(D) Print 1,
(E) now i=1 and it is less than 2,
(F) now increment it to 2.
(G) Print 2.
(H) now i=2 and it is not less than 2, so drop out of the for loop.
(I) evaluate the while j = 0 and it is less than 2, now increment j to 1 and go back to (A).

Now in (I) when j=2 then it does not go back to (A) anymore and the program is done.

Mark