Doubt with operator '=' several times in a statement


I would like to know why this code prints 3,1 and not another value:

Point a,b,c;

b = new Point(2,4);
a = new Point(3,1);
c = b = a;
c = new Point(1,2);
asked by Negra 05.09.2016 в 05:20

1 answer


The assignment operator ( = ) is applied from right to left. That is, on the left operand the operation is performed taking the operand to the right.

In the specific case of c = b = a; the variable a is not modified by the assignment. The variables c and b in this case are assigned the object referenced by a .

The sentence is evaluated as c = (b = a) as indicated by @JoseAntonioDuraOlmos.

Now, your variables ( a b c ) are references to objects Point . They are not the object itself.

When you make c= New Point(1,2) you create a new object Point and this new object is referenced by c . You are not accessing the object referenced by c . It is not the semantics of = in the language for this case.

That's why when you print on the screen a you see (3,1) .


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answered by 05.09.2016 в 06:46