freaky output!

This is a discussion on freaky output! within the C Programming forums, part of the General Programming Boards category; Can any one tell me why the out put is "1 40 0" and not "1 40 1" Code: main() ...

  1. #1
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    freaky output!

    Can any one tell me why the out put is "1 40 0" and not "1 40 1"
    Code:
    main()
    {
         int x;
         printf("%d%d%d",x<=50,x=40,x>=10);
         getch();
    }
    cheers!

  2. #2
    Woof, woof! zacs7's Avatar
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    It's undefined.

    The standard emposes no order of which arguments are evaulated, that's up to the compiler (and optimization it might do*).

    * Which may change the result when optimizations are on or off for example.

  3. #3
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    You have not initialized x so it's value is undefined. Also it is undefined what the order of argument evaluation is, so you do not know whether or not x=40 happens before x>=10, and obviously in this case it doesn't.

    Why would you be doing something like this?

  4. #4
    Woof, woof! zacs7's Avatar
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    The obvious "fix" is;

    Code:
    int main(void)
    {
       int x = 2;
       int a, b;
    
       a = (x <= 50);
       x = 40;
       b = (x >= 10);
    
       printf("&#37;d %d %d\n", a, x, b);
       return 0;
    }

  5. #5
    DESTINY BEN10's Avatar
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    Can any one tell me why the out put is "1 40 0" and not "1 40 1"
    it completely depends on the compiler used.also as x is undefined , any garbage value is taken up and according to this value & the order of argument evaluation the compiler produces the output.

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