quick question regarding the '==' sign.

This is a discussion on quick question regarding the '==' sign. within the C++ Programming forums, part of the General Programming Boards category; can you have a situation like Code: int a = 3; int b = 3; int c = 3; if ...

  1. #1
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    quick question regarding the '==' sign.

    can you have a situation like

    Code:
    int a = 3;
    int b = 3;
    int c = 3;
    
    if (a == b == c){
          cout<< "yes";
    }
    or does it have to be

    Code:
    if (a == b && a == c){
          cout<< "yes";
    }

  2. #2
    C++ Witch laserlight's Avatar
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    It can be the former (but you may get a result which you did not expect), but it should be the latter.
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  3. #3
    Kernel hacker
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    The second one will do what you want. The first one does:
    Code:
    a == (b == c)
    Which can be re-written as:
    Code:
    temp = (b == c);  // Makes a value of 0 or 1. (parenthesis not strictly necessary)
    a == temp;
    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  4. #4
    Jack of many languages Dino's Avatar
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    So, to clarify (for myself),
    Code:
    a==b==c ;
    results in false, even through a==b is true and b==c is true. Correct?

    Todd

  5. #5
    C++ Witch laserlight's Avatar
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    results in false, even through a==b is true and b==c is true. Correct?
    Correct, except for special cases, e.g., a = b = c = 1.
    C + C++ Compiler: MinGW port of GCC
    Version Control System: Bazaar

    Look up a C++ Reference and learn How To Ask Questions The Smart Way

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