Thread: Can somebody help me...!!!! This is terrible!!!

  1. #1
    Registered User
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    Unhappy Can somebody help me...!!!! This is terrible!!!

    Arggg........I've stucked on this problem for 2 weeks.....my question is:

    I'm supposed to use calloc() or malloc() to create a dynamic data structure (a.k.a: Dynamic 2D Array).

    I'm able to allocate memory sucessfully to create a 2D array, but my problem is: How do I insert values into the empty array which I created using calloc() or malloc()....??


    If I were to read the data from a file and place the data into the Dynamic 2D array......ermmm...how to do it..??


    I'm new in C, so hopefully anyone of you who see my post, please kindly give me your advice....and don't leave me alone....All help will be GREATLY appreciated.......Thanks!!!








    Assist Me!

  2. #2
    ---
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    Code:
    #include <stdlib.h>
    #define N 5 // Number of array elements
    
    int main(void){
      char *array = malloc(sizeof(char) * N);
      if(array){
        // insert data into array here
    
      }
      
      return 0;
    }

  3. #3
    and the hat of int overfl Salem's Avatar
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    Well if you've done the job properly (which you didn't show us), then you simply do
    Code:
    int **twod;
    // some malloc calls (which you've done)
    twod[0][0] = 1;  // set the first element of the array
    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.

  4. #4
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    *phew*
    I thought I did something wrong for a second there.

  5. #5
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    Oh...I'm sorry that I didi not show my codes because I thought that will be very messy......

    these are my codes......

    hey...wait.....what's wrong.....I can't post my codes here..!!!!
    They say please use code tags to format your code properly when I clicked "preview"....



    Explanation: I used calloc() to create a dynamic 2-D array first. Then, I'm supposed to get the data from file: Filename.data and place the data accordingly into the 2-D array.

    Hence, I used fgets() to get the first row of data first. Then, use strtok() to get the values from the row of data one by one and intend to place them into the 2-D array.

    But my major problem is: my table is declared in float and when I use strtok(), the datatype of the datas extracted from the original dataset become "char" datatype.

    Hence cannot be placed into the 2-D array anymore....

    My concern is: How to convert the datas back to float first b4 assigning them into the 2-D array?

  6. #6
    & the hat of GPL slaying Thantos's Avatar
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    Quote Originally Posted by AssistMe
    hey...wait.....what's wrong.....I can't post my codes here..!!!!
    They say please use code tags to format your code properly when I clicked "preview"....
    http://cboard.cprogramming.com/showthread.php?t=25765

  7. #7
    It's full of stars adrianxw's Avatar
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    Most newbies code is messy, we are used to seeing that. You should post your code. People who come here and don't show their own efforts generally don't get much help.
    Wave upon wave of demented avengers march cheerfully out of obscurity unto the dream.

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