Thread: Need help to understand Arrays

  1. #1
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    Need help to understand Arrays

    Alright, so I read through the Arrays tutorial on this website -
    Arrays in C and C++ - Cprogramming.com

    And so I tried using the tutorial codes -

    Code:
    #include <iostream>
    
    
    using namespace std;
    
    
    int main()
    {
      int x;
      int y;
      int array[8][8]; // Declares an array like a chessboard
    
    
      for ( x = 0; x < 8; x++ ) {
        for ( y = 0; y < 8; y++ )
          array[x][y] = x * y; // Set each element to a value
      }
      cout<<"Array Indices:\n";
      for ( x = 0; x < 8;x++ ) {
        for ( y = 0; y < 8; y++ )
          cout<<"["<<x<<"]["<<y<<"]="<< array[x][y] <<" ";
        cout<<"\n";
      }
      cin.get();
    }
    And when the program is launched, it prints all this-

    Need help to understand Arrays-arrays-jpg

    So.., here is what I don't understand. In the left brackets of each column ( I assume it's where the x's are) shows 0 - 7. But in the right brackets of each column ( I assume it's where the y's are) show 0 in the first column and 1 on the second column, 2 on the third column and so on... That is what I don't understand.

    huh ?_? huh <- May someone please give me an easier explanation. Thanks.
    Attached Images Attached Images Need help to understand Arrays-arrays-jpg 

  2. #2
    Programming Wraith GReaper's Avatar
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    The left brackets hold the row, while the right brackets hold the column. Can't you see a pattern on how these values are printed?
    Devoted my life to programming...

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    Quote Originally Posted by GReaper View Post
    The left brackets hold the row, while the right brackets hold the column. Can't you see a pattern on how these values are printed?
    I still don't understand. And it's the numbers that has my fingers scratching my head.

  4. #4
    Programming Wraith GReaper's Avatar
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    Quote Originally Posted by Conti View Post
    I still don't understand. And it's the numbers that has my fingers scratching my head.
    A 2D matrix has rows and columns. Think of it like a chess board for example:
    Code:
      A B C D E F G H
    1                 1
    2                 2
    3                 3
    4                 4
    5                 5
    6                 6
    7                 7
    8                 8
      A B C D E F G H 
    How do you determine, with words, where a pone is or what your next movement will be?
    Devoted my life to programming...

  5. #5
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    Quote Originally Posted by GReaper View Post
    A 2D matrix has rows and columns. Think of it like a chess board for example:
    Code:
      A B C D E F G H
    1                 1
    2                 2
    3                 3
    4                 4
    5                 5
    6                 6
    7                 7
    8                 8
      A B C D E F G H 
    How do you determine, with words, where a pone is or what your next movement will be?
    Ah. I understand now. +1 to you chap ^.^

  6. #6
    C++まいる!Cをこわせ!
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    Another way of visualizing it (which scales beyond 2 dimensions) is that you have some small boxes with some value in them.
    Then you take those boxes and put them into one big box.
    And finally, you create several of those big boxes (all of which contains all those small boxes inside them).
    For every dimension you add, you repeat this.
    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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