Question

how can I use "malloc" for 2d matrix?

Answer 1

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#include <stdio.h>

#include <stdlib.h>

int main()

{

    unsigned int i, j, nrows = 2;

    unsigned int ncolumns = 3;

    

    unsigned int **array;

    

array = malloc(nrows * sizeof(unsigned int *));

if(array == NULL)

{

fprintf(stderr, "out of memory\n");

return -1;

}

for(i = 0; i < nrows; i++)

{

array[i] = malloc(ncolumns * sizeof(int));

if(array[i] == NULL)

{

fprintf(stderr, "out of memory\n");

return -1;

}

}

array[0][0] = 100;

array[0][1] = 101;

array[0][2] = 102;

array[1][0] = 110;

array[1][2] = 112;

array[1][1] = 111;

for(i = 0; i < nrows; i++)

    for(j = 0; j < ncolumns; j++)

            printf("\nArray[%d][%d] = %d", i, j, array[i][j]);

    return 0;

}