Confused with array size

This is a discussion on Confused with array size within the C Programming forums, part of the General Programming Boards category; Hi, I'm starting to get confused here..if I want an array to hold 2 values, then should I write int ...

  1. #1
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    Confused with array size

    Hi,

    I'm starting to get confused here..if I want an array to hold 2 values, then should I write int values[1] or int values [2] ? I'm confused because of the 0 index.

    Also, when I wish to have an array of string, then is it just char values[n][20] (where 20 is the number of maximum characters and n is how many strings I have in the array) ?

  2. #2
    C++ Witch laserlight's Avatar
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    You should write:
    Code:
    int values[2];
    But if you want to access those elements of the array, it would be values[0] and values[1]. values[2] does not exist.
    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.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

  3. #3
    Deathray Engineer MacGyver's Avatar
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    Declare with the number of elements you want. If you declare n elements, then you have elements ranging from index 0 to n-1, inclusive.

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    Quote Originally Posted by desmond5 View Post
    Hi,

    I'm starting to get confused here..if I want an array to hold 2 values, then should I write int values[1] or int values [2] ? I'm confused because of the 0 index.
    As everyone mentions, the syntax is array[length_of_array] and then you have length_of_array-1 elements because they count from 0.

    Also, when I wish to have an array of string, then is it just char values[n][20] (where 20 is the number of maximum characters and n is how many strings I have in the array) ?
    The syntax would be, I believe, char values[num_of_string][length_of_strings];
    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.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

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    It's easier I believe, to think of a 2d array as being Array[rows][columns]. Internally, the compiler handles this quite differently, but it can be thought of thematically, as rows and columns, and was designed with that in mind.

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