What's the output?

Question

https://code.sololearn.com/c45RgdPzM4GR/?ref=app

Answer 1

Hmm. Think this like this:
int y = ++x * ++x is equal to:
x = x + 1 //6
x = x + 1 //7
int y = x * x //49
So the multiplication happens after increments happen. This is because prefix increments (++x) happens before the statement executes.

Answer 2

x becomes 6 at the first part and then 7 at the second part. After that the multiplication happens so it is 7*7. I think this is why.

Answer 3

Ah, also, the output will be 742 in Java, C# languages like your prediction. C++ has some undefined behaviour. For more information again check this site:

https://stackoverflow.com/questions/6457130/pre-post-increment-operator-behavior-in-c-c-java-c-sharp

Answer 4

but it should be.. 742 according to logic. which says
++x(value 6)*++x(value7)
that's 42

Answer 5

exactly.. but why we get 7*7=49 as output

Answer 6

but the 1st value of ++x should be taken as 6 & next ++x should be taken as 7, what's the reason of both being taken as 7, but it's not in the other cases of x++ or --x.

Answer 7

This time x++ is postfix and it effects the right x value but doesn't increment itself before the statement executes. You can check this link to get deep information about these:

https://stackoverflow.com/questions/7031326/what-is-the-difference-between-prefix-and-postfix-operators

Answer 8

okay okay got u.. thanks!

Answer 9

x=5;
y=x++*x;
cout<<x<<y;
gives 630 ie 6, 5*6 as o/p .
why not it takes the 6 as both the values?