using double codes in assigning value to an int variable

This is a discussion on using double codes in assigning value to an int variable within the C Programming forums, part of the General Programming Boards category; Code: main() { int i = "a"; printf("%d %c",a,a); getch(); } the output shows a no. 170 and a ASCII ...

  1. #1
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    using double codes in assigning value to an int variable

    Code:
    main()
    {
       int i = "a";
       printf("%d       %c",a,a);
       getch();
    }
    the output shows a no. 170 and a ASCII character corresponding to it. Even if we change the character we get the same no. 170. I know I am int variable wrongly but it is just a curiosity why does it shows 170. If we use float or char variable it shows an error.
    I am usinng turbo c++ in windows xp.

    thanks a lot
    bye n take care

  2. #2
    and the hat of wrongness Salem's Avatar
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    All you're printing is the address of where the string is stored.
    Or in the case of %c, the LSB of the address, expressed as a char.

    Since the compiler seems to put the first string it finds in the same place in memory, the actual content of the string is irrelevant.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

  3. #3
    Registered User ssharish2005's Avatar
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    I would dought that program will atleast compile. a is a variable which us undeclared. Din't your compile complain you anything about.

    ssharish2005

  4. #4
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    @Salem Thanks Salem, I somewhat understood your point, one thing is still there, why does using int variable does not give a error but using float or char gives error.

    @ssharish2005, the compliler doesn't give any error in this case, but if we use float or char in place of int then it gives error.

  5. #5
    and the hat of wrongness Salem's Avatar
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    Yeah, there is so much wrong with the code that analysis is nigh on impossible.
    It was probably just typed from memory, rather than a more accurate copy/paste from the code editor.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

  6. #6
    Woof, woof! zacs7's Avatar
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    Quote Originally Posted by hitesh_best View Post
    @Salem Thanks Salem, I somewhat understood your point, one thing is still there, why does using int variable does not give a error but using float or char gives error.

    @ssharish2005, the compliler doesn't give any error in this case, but if we use float or char in place of int then it gives error.
    He was asking where 'a' came from (the variable),

    Code:
    main()
    {
       int i = "a";
       printf("%d       %c",a,a);
       getch();
    }
    But I assume you meant to print i not a

  7. #7
    and the hat of wrongness Salem's Avatar
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    Probably because your ancient compiler will silently convert a pointer to an int without complaining.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

  8. #8
    The larch
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    In short there is a big difference between double quotes " and a single quote '
    I might be wrong.

    Thank you, anon. You sure know how to recognize different types of trees from quite a long way away.
    Quoted more than 1000 times (I hope).

  9. #9
    Kernel hacker
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    To the original poster: If you enable WARNINGS in your compiler, it will definitely tell you that you are converting a pointer into an integer, which is probably not really what you wanted.

    --
    Mats

  10. #10
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    Oh yes, there is a mistake in the code.

    It should have been variable i in the print statement, instead of a.

  11. #11
    Day Dreamer
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    Quote Originally Posted by hitesh_best View Post
    Oh yes, there is a mistake in the code.

    It should have been variable i in the print statement, instead of a.
    which means you actually posted the code without even looking at it once or bothering to compile it?
    Or just typed it from memory and never bothered to check it.

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