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I`m stuck in Korea in my apartment, so anybody want to explain this to me
The sum is
X = 22
X + 3 / (++X + 2)
Now when I work it out, i do the following
X + 3 / (23 + 2) (23 because its X + 1 basicly)
X + 3 / (25)
X + .12
22.12
Now the answer according to C++ should be
23
I wish I had studied in math alot more all those years ago!
Idiots answer and theory please and any links to a good program that can explain math problems in steps so i can see where I am going wrong!
Thanks:confused:
Make sure X is a float, and not an int. If I'm not mistaken, int types ignore anything beyond the decimal point, which could explain why you get that weird answer (It considers 3 / 25 to be > 0, so makes it 1).
Secondly, I suspect that it's really 3 / (22 + 2), or, 3 / 24. Again, if I recall correctly, "++X" increases X by one after the rest of the code is executed. "X++" would increase it by one beforehand, which is what I think you want.
So:
X = 22;
Z = X + 3 / (++X + 2);
// Z = 22.125 if it is a float, 23 if not.
// X = 23
X = 22;
Z = X + 3 / (X++ + 2);
// Z = 22.12 if it is a float, 23 if not.
// X = 23
Hope that helps.
Okay its an Int,
so basicly my math is right but instead of 22.125 it rounds up (not down) and makes it 23...
Great, I thought I was going crazy.
Just for referance the code is... (with x being int)
Cut & Paste
----------------------------------------------
x = 22;
answer = x + 3 / (++x + 2);
----------------------------------------------
so the answer is 22.125 rounded up.
Ints always round up. (I guess you are saying).
Thanks for the help.
Okay think i have it a bit more in my head
x = 22;
answer = x + 3 / (++x + 2);
X value is 22
(++X + 2)
Inceases X value to 23 for the function
so it is 23 + 3 / 25
23 + .125
its a Int so it rounds it down (that makes more sense)
so its 23.
That right?? ;)
:confused: :rolleyes:
Sorry, I got it the wrong way around.
X = 22;
answer = X + 3 / (++X + 2);
is the same as
X = 22;
X = X + 1; // X = 23 now
answer = X + 3 / (X + 2); // answer = 22.12
However:
X = 22;
answer = X + 3 / (X++ + 2);
is the same as
X = 22;
answer = X + 3 / (X + 2); // answer = 22.125
X = X + 1; // X = 23 now
That's the wrong way around.Quote:
Originally posted by eldren
Secondly, I suspect that it's really 3 / (22 + 2), or, 3 / 24. Again, if I recall correctly, "++X" increases X by one after the rest of the code is executed. "X++" would increase it by one beforehand, which is what I think you want.
++x will increment x and then evaluate the rest of the expression.
x++ will evaluate the expression then increment x.
*prods* See my 10:02 post? But, yes, I did get it wrong, first time round.Quote:
Originally posted by DaBeeeenster
That's the wrong way around.
++x will increment x and then evaluate the rest of the expression.
x++ will evaluate the expression then increment x.