post decrement in while loop

[dasarisrikar]

I hav one doubt regarding post decriment,the code in c is as follows.............

void main()
{
clrscr();
while(i--!=6)
i=i+2;
printf("%d\n",i);
getch();
}

I know the output is 5, but i read in a book dat the post incriment or decrement operators are evaluated after reaching semicolon(.....but in while condition,the ondition fails so it wont execute the next line so, directly reaches printf.Till now there is no semicolon still the i value is decresed......wts da reason...can u sugest me..?

Thanks & Regards.

[Banfa]

but i read in a book dat the post incriment or decrement operators are evaluated after reaching semicolon

This is a very simplified and wrong statement about the way post increment/decrement work.

The variable is incremented or decremented once the expression it is in has been evaluated. The the case of the while loop the expression has to be evaluated in order to tell if the follow of control should go into the loop or not, once this is done and a true or false result obtained the variable i is decremented.

[dasarisrikar]

thanks banfa....