clear int m?

This is a discussion on clear int m? within the C++ Programming forums, part of the General Programming Boards category; my program is looping because int m = (any integer) stops it from pausing because a condition is being satisfied. ...

  1. #1
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    clear int m?

    my program is looping because
    int m = (any integer)
    stops it from pausing because a condition is being satisfied.

    How do I clear m so that
    m = (nothing)

  2. #2
    Programming Wraith GReaper's Avatar
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    Quote Originally Posted by mikeyp View Post
    How do I clear m so that
    m = (nothing)
    ????

    A variable always contains something!!! It's not a pointer!
    But you could set it to 0 in order to be casted to false when checked:

    Code:
    if (!m) {/*...*/} // true when m = 0, false otherwise
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  3. #3
    Algorithm Dissector iMalc's Avatar
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    So you have a value that consists of 32 bits (I'm going to assume 32 bits anyway) which are either one or zero and you want it to equal "nothing"?
    Well you'll just have to invent some combination of 32 ones and zeros that you'd like to mean "nothing" and assign that. Well you could set all 32 bits to zero I guess, in other words assign the value zero to m.

    Perhaps you can just assign a value that stops the condition from being satisfied.
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    Programming Wraith GReaper's Avatar
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    Actually, zero is (nothing), so it's safe and meaningful to set m to zero and do what i told you ( some times i guess )
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  5. #5
    spurious conceit MK27's Avatar
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    You could also use an int pointer, and than can be set to NULL, which is not the same as having the pointer contain 0.
    Code:
    int n = 0, *x = &n;
    x = NULL;
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    Quote Originally Posted by Sipher View Post
    Actually, zero is (nothing), so it's safe and meaningful to set m to zero and do what i told you ( some times i guess )
    0 is not nothing, it's an integer value just like 1 and 12345 are. There is no possible way to have an int containing nothing.
    It is often used to represent nothing, but that's not the same thing as being nothing.

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    So does that mean that when I create

    int m;

    its value is 0 anyway?

  8. #8
    Captain Crash brewbuck's Avatar
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    Quote Originally Posted by mikeyp View Post
    So does that mean that when I create

    int m;

    its value is 0 anyway?
    No. Its value is undefined. That doesn't mean it has no value, but it means the value is unpredictable.
    Code:
    //try
    //{
    	if (a) do { f( b); } while(1);
    	else   do { f(!b); } while(1);
    //}

  9. #9
    and the hat of sweating
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    You could also create a class that represents an int, but also lets you set the state of the class to 'nothing'. Personally, I think that's overkill. Just use 0, or a NULL pointer.
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  10. #10
    Registered User UltraKing227's Avatar
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    yep, brewbuck is right, int m; gives an unpredictable number. E.G it may contain
    10 by default and 49 on another computer.

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