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Evaluation problem

 
Ranch Hand
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Can somebody make me understand how the value of j is evaluating in the commented line

class incdec
{
public static void main(String[] args)
{
int j=5;
int k;
k=j++ + --j;// How it is evaluation
k++;
System.out.println("k="+k);
}
}
 
Bartender
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With the post increment operator when used in an expression value will be incremented/decremented by one but the previous value is used.
So the line,

can be interpreted as,

 
Ranch Hand
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remember this:
post-increment -> participates in expression and then increment
pre-increment -> increment and participate in expression

int j=5;
int k;
k=j++;
System.out.println("k="+k); // prints 5
(or)
int j=5;
int k;
k=++j;
System.out.println("k="+k); // prints 6


j++ + --j;
5 + (6-1)5 = 10



 
Ranch Hand
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It's pretty siple - the output is 11.
[value 5 is taken(it's post incrementing so we take j value in this expression and j+1 in the next expression with j) + --j(value 5 is taken - it's predecrementing but j has value of 6 because it was postincremented)]
 
Rajesh k Jha
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Hi Ravi,
Your example really clarified all my steps of postincrement and preincrement.
Thanks a lot..
 
Sheriff
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Please Use Code Tags when you post a source code...
 
Consider Paul's rocket mass heater.
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