Thread: double arrays

  1. #1
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    double arrays

    I need an array of dimension NxN but I need to malloc instead of doing 'int a[N][N];' and read in integers. I tried the following:

    int ..........;
    ...
    a=(int **)malloc(N*sizeof(int**));
    and (a+i+j) to store the scanned value using nested for loops. It's not working since a+1+0 is the same as a+0+1

    could anyone help? C or C++
    Thanks,

    xer
    *new programer*

  2. #2
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    first the proper declaration is
    int **a;
    first you have to allocate space so that a can hold N pointers
    a= mallco(N*sizeof(int *));
    the loop through i to allocate space for N elements in each of of the N pointers
    for(i=0;i<N;i++)
    a[i]=malloc(N*sizeof(int));


    a[i] or *(a+i) is the pointer to the ith row
    so the i,j element is *(*(a+i)+j) or a[i][j] or *(a[i]+j),

  3. #3
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    Guest
    thanks, I just figured out how to do it.

    xer

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