Thread: How do I calculate the number of spaces...

  1. #1
    Programming Ninja In-T...
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    Question How do I calculate the number of spaces...

    How do I calculate the current number of spaces between two columns of data in a line of a file, such so that I can determine how many additional spaces it will take to bring the second column to position 22 (0-based), so that I can change the line to put the correct number of spaces between the two columns of data?

    I already have the position of the last non-spc-char of the first column, and also the position of the first non-spc-char of the second column. Do I just subtract the former from the latter? That would get the number of existing spaces, but then what? How do I figure out how many additional spaces I need to bring the second column of data to position 22?
    Last edited by Programmer_P; 04-03-2011 at 01:02 PM.
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  2. #2
    C++まいる!Cをこわせ!
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    You could try using I/O manipulators to pad. std::setw and std::fill, I believe.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
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    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

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  3. #3
    Algorithm Dissector iMalc's Avatar
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    Surely you must know the string length of the data from each column. Subtract that from the desired string length and append that number of spaces. I can't see where any difficulty youre having might be. Code might help.
    Last edited by iMalc; 04-04-2011 at 12:39 AM.
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