What does this symbol mean? ==

Question

I've seen in duel this symbol ==, but it was in an equation like that '<< cout << (a+(b==c))'.

I can't understand what is the function of this one.

I've seen this symbol before in manual, for example: 'if (a==c)'.

And i understand, that they both have different functions.

What does this symbol mean in such an equation '(a+(b==c))'?

P.S. #sry4myenglish

Answer 1

Poorie

For a + (b == c), the result is a or a + 1 depending on whether b == c is true or false (2 == 4 would be false, resulting in 0, resulting in the final answer being a, while 3 == 3 would be true, resulting in 1, resulting in the final answer being a + 1). So:

x = 2 + (3 == 3) -> x = 2 + true -> x = 2 + 1 -> x = 3
x = 2 + (3 == 1) -> x = 2 + false -> x = 2 + 0 -> x = 2

Besides ==, you can also use other conditional operators, like !=, >, <, etc.

For the a + (b == c) * (d / e) expression, you are correct. It could be a in the case that b == c is false, resulting in a + 0 * (d / e), which is just a. It could also be a + (d / e) in the case that b == c is true, resulting in a + 1 * (d / e), which is just a + (d / e).

Hope that helps! :)

Answer 2

The expression b == c evaluates to either 0 (false), 1 (true), or an error occurs. With that in mind, you can add another integer (or something else), perhaps integer a.

:)

Answer 3

false: 0
true: 1
So you can use conditions in calculations like +-*/%.

Answer 4

Just to add to Lunar Coffee's excellent answer, here is some code to help you learn:
https://code.sololearn.com/ch3scU0mcxh6/#c

Also, I think you meant 'a+(b==c)+(d/e)' rather than 'a+(b==c)*(d/e)'?

Answer 5

LunarCoffee
Thank you for your answer.
I hope, that i understood right. It means, that for example in this equation 'a+(b==c)' the answer is 'a'?

And what about the equation, for example 'a+(b==c)*(d/e)'? The answer is again 'a' or 'a+(d/e)'.

Jesus, it's quite hard.

Answer 6

LunarCoffee
Jesus, you are god! Now i understand it, like a black word on the white list! You are the best!

Answer 7

it is the comparison operator "is equal to" which returns true (which has the value 1) or false (which has the value of 0). in the equation given, a would be incremented by one only if b and c are equal,