Thread: order of evaluation of C-expression

  1. #1
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    order of evaluation of C-expression

    Can anyone explain why output of following program excerpt gives value '6' for x ?

    int x=8;
    x-=--x-x--;//how this statement will be processed
    printf("%d",x);

  2. #2
    C++ Witch laserlight's Avatar
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    Because the behaviour is undefined as x is modified more than once between consecutive sequence points.
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
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