C - dynamic arrays -

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i don't quite understand how pointers work c arrays. here's code got:

int arrayone[] = {1, 2, 3}; int arraytwo[] = {4, 5, 6, 7};  int **arraythree = (int **)malloc(2 * sizeof(int)); arraythree[0] = arrayone; arraythree[1] = arraytwo;  (int = 0; < 2; i++) {     int *array = arraythree[i];     int length = sizeof(array) / sizeof(int);     (int j = 0; j < length; j++)         printf("arraythree[%d][%d] = %d\n", i, j, array[j]); }

i have expected output following:

arraythree[0][0] = 1 arraythree[0][1] = 2 arraythree[0][2] = 3 arraythree[1][0] = 4 arraythree[1][1] = 5 arraythree[1][2] = 6 arraythree[1][3] = 7

what prints out is:

arraythree[0][0] = 1 arraythree[0][1] = 2 arraythree[1][0] = 4 arraythree[1][1] = 5

why?!

sizeof(array) size of pointer, happens twice size of int on platform.

there's no way length of array in c. have remember yourself.


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