Help I'm Hopelessss

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  1. #1
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    Unhappy Help I'm Hopelessss

    I'm sorry I can't reply for some reason so if u feel u need to replace this go ahead.


    I'm messing around with the NOT !.
    At the first place I did like this !(1 || 0) and that suppose to be true I guess, but it doesn't recognize the '!'. Then I did a thread here and some guy told me it suppose to be (!true) but that didn't work either so what SHOULD I DO?!?!?!? pls help


    HELPPPPP pls

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    oh and if it is (!true) so how do I make it like first evaluate (1 || 0) then evaluate NOT. (1 || 0) = true but NOT makes it false.

  3. #3
    Cat without Hat CornedBee's Avatar
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    !(1 || 0) and that suppose to be true I guess
    No, it's not.

    What do you mean by "not recognize"? You get a compile error?
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
    - Flon's Law

  4. #4
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    (1 || 0) evaluates to true. !(1 || 0) evaluates to false.

    if you do this:
    Code:
    if !(1 || 0)
    you will get a compile error. Do this:
    Code:
    if (!(1 || 0))

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    Thankkkkss

    WOOWW thanks it's really (!(1/0)) and recognize = identify

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    oh 1 last question: how do I make && evaluate after ||? means: if I do (1 || 1 && 0) that's not like 1 || 1 = 1 && 0 = 0

    it's 1 && 0 = 1 then 1 || 1 = 1
    I want AND to be evaluate before OR, how do I do that?

  7. #7
    The larch
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    = is assignment, == is comparison for equality.
    To change the order in which subexpressions are evaluated, use () just like you do in math expressions.
    I might be wrong.

    Thank you, anon. You sure know how to recognize different types of trees from quite a long way away.
    Quoted more than 1000 times (I hope).

  8. #8
    C++まいる!Cをこわせ!
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    Quote Originally Posted by mat13mat View Post
    WOOWW thanks it's really (!(1/0)) and recognize = identify
    if something
    Is illegal.
    if (something)
    Is legal.

    Therefore, the error was that you did not write the if properly.

    Here's an example of your second q:
    if ( 1 || (1 && 0) )
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

  9. #9
    CSharpener vart's Avatar
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    Here's an example of your second q:
    if ( 1 || (1 && 0) )
    which is equivalent to
    if ( 1 || 1 && 0 )
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  10. #10
    C++まいる!Cをこわせ!
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    I think I've an idea now how it was supposed to be. If && is to be first, then place it first:
    if ( (1 && 0) || 1 )
    Parenthesises make the expression less ambiguous, so I'd definitely recommend them, even if they are not required.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

  11. #11
    Cat without Hat CornedBee's Avatar
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    mat13mat: You say you want to evaluate && after ||, but then you proceed to give examples of the opposite.

    If && is to be first, then place it first:
    That may help readability, but has zero effect on actual semantics. && always comes first because it has a higher precedence than ||. If you want to change this, you have to add extra parentheses around the OR expression.
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
    - Flon's Law

  12. #12
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    I don't know if some1 will answer this here so I'll post a thread too, gm do w/e u want.
    If I make 2 files in 1 project, and I execute it, but I want to execute only 1 file how do I do it?
    I made a project with 2 files in it, 1 is int main() and 1 is int submain() now how do I execute the submain file? only int main() executes and I get to errors pls help.

  13. #13
    C++まいる!Cをこわせ!
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    Functions needs to be called.
    Int main gets called upon program startup. Any other function you must call manually. There are not special.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

  14. #14
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    What C++ book are you using that doesn't cover this?

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