Defined constants questions

This is a discussion on Defined constants questions within the C Programming forums, part of the General Programming Boards category; Why does this code = 27 instead of 21 7*7*7=21 Code: #include <stdio.h> #define x 5+2 main(){ int i; i=x*x*x; ...

  1. #1
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    Defined constants questions

    Why does this code = 27 instead of 21

    7*7*7=21

    Code:
    #include <stdio.h>
    #define x 5+2
    main(){
    	int i;
    	i=x*x*x;
    	printf("%d",i);
    	getchar();
    	getchar();
    }

  2. #2
    SAMARAS std10093's Avatar
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    5 + 2 * 5 + 2 * 5 + 2.
    This is what you said your code to do.
    Read more here.
    Code - functions and small libraries I use


    It’s 2014 and I still use printf() for debugging.


    "Programs must be written for people to read, and only incidentally for machines to execute. " —Harold Abelson

  3. #3
    SAMARAS std10093's Avatar
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    Oh and also, 7 * 7 * 7 is not 7*3, but 7³ = 343, that's why you need to wrap your value in parenthesis like this,

    Code:
    #define x (5+2)
    This was a good question you made
    Code - functions and small libraries I use


    It’s 2014 and I still use printf() for debugging.


    "Programs must be written for people to read, and only incidentally for machines to execute. " —Harold Abelson

  4. #4
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    Haha, can't believe i didn't see the little math operations in that lol. Thank for the help

  5. #5
    SAMARAS std10093's Avatar
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    You are not the first one who did not, neither the last one

    You are welcome
    Code - functions and small libraries I use


    It’s 2014 and I still use printf() for debugging.


    "Programs must be written for people to read, and only incidentally for machines to execute. " —Harold Abelson

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