assign value of pointer array

This is a discussion on assign value of pointer array within the C Programming forums, part of the General Programming Boards category; Code: char *name[4]; int i = 0; while ( i < 4) { int k = 0; while (k < ...

  1. #1
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    assign value of pointer array

    Code:
     char *name[4];
     int i = 0;
     while ( i < 4)
     {
         int k = 0;
         while (k < 4)
          {
                *(name[i]+k) = 'c';
                k++;
           }
         
         i++;
      }
    result: error!

    why?
    Last edited by zcrself; 08-17-2009 at 01:53 AM.

  2. #2
    Woof, woof! zacs7's Avatar
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    Because name[4] is out of bounds.

    You might want to look-up what i++ and k++ actually mean.
    More specifically, what the Boolean expression (i++ < 4) means...
    Code:
    int i = 3;
    if(i++ < 4)
       printf("I solved my own question\n");

  3. #3
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    Not sure what you are trying to do but the code is attempting to insert values at name[4] which is outside the array index

    [edit: Beaten to the punch by zacs7]
    Last edited by strider1974; 08-17-2009 at 01:51 AM.

  4. #4
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    Quote Originally Posted by zacs7 View Post
    Because name[4] is out of bounds.

    You might want to look-up what i++ and k++ actually mean.
    More specifically, what the Boolean expression (i++ < 4) means...
    Code:
    int i = 3;
    if(i++ < 4)
       printf("I solved my own question\n");
    Code:
     char *name[4];
     int i = 0;
     while ( i < 4)
     {
         int k = 0;
         while (k < 4)
          {
                *(name[i]+k) = 'c';
                k++;
           }
         
         i++;
      }

  5. #5
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    Quote Originally Posted by strider1974 View Post
    Not sure what you are trying to do but the code is attempting to insert values at name[4] which is outside the array index

    [edit: Beaten to the punch by zacs7]
    Code:
     char *name[4];
     int i = 0;
     while ( i < 4)
     {
         int k = 0;
         while (k < 4)
          {
                *(name[i]+k) = 'c';
                k++;
           }
         
         i++;
      }

  6. #6
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    Code:
    char *name[4][4];
     int i = 0;
     while ( i < 4)
     {
         int k = 0;
         while (k < 4)
          {
                *(name[i]+k) = 'c';
                k++;
           }

    i++;
    }




    //now u r code is oky.....u r using one dimention pointer array but u using two loop nested it not work....

    using two dimention then try.....

  7. #7
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    Quote Originally Posted by karimmughal View Post
    Code:
    char *name[4][4];
     int i = 0;
     while ( i < 4)
     {
         int k = 0;
         while (k < 4)
          {
                *(name[i]+k) = 'c';
                k++;
           }

    i++;
    }




    //now u r code is oky.....u r using one dimention pointer array but u using two loop nested it not work....

    using two dimention then try.....
    That is 3 dimension
    Code:
    char *name[4][4];

  8. #8
    DESTINY BEN10's Avatar
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    Quote Originally Posted by zcrself View Post
    Code:
     char *name[4];
     int i = 0;
     while ( i < 4)
     {
         int k = 0;
         while (k < 4)
          {
                *(name[i]+k) = 'c';
                k++;
           }
         
         i++;
      }
    result: error!

    why?
    What are you trying to achieve? name[i] is an address, adding k to it will try to access any random memory which results in segf.
    HOPE YOU UNDERSTAND.......

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  9. #9
    C++まいる!Cをこわせ! Elysia's Avatar
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    Everyone who posted and modified the original in the beginning needs to take a crash course in C 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.

  10. #10
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    Everyone who posted and modified the original in the beginning needs to take a crash course in C strings.
    Everyone? I only see one poster that attempted to modify the original code (karimmughal's post). Everyone else simply pointed out the 2 mains issues with the code.
    bit∙hub [bit-huhb] n. A source and destination for information.

  11. #11
    C++まいる!Cをこわせ! Elysia's Avatar
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    Everyone who modified it, yes. I see that there is only one aside from the OP, so that's a total of two who needs to take a crash course.
    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.

  12. #12
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    The only problem I see from the original is that there was no storage allocated for name strings. There was never any bounds issue.

  13. #13
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    Quote Originally Posted by nonoob View Post
    The only problem I see from the original is that there was no storage allocated for name strings. There was never any bounds issue.
    I believe the code in the original post was edited.
    bit∙hub [bit-huhb] n. A source and destination for information.

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