c - Can anyone please explain difference between ptr+1 and ptr[0]+1 -


assuming sizeof integer 4 bytes , sizeof(int *) 8 bytes , i'm not getting why ptr +1 moves forward size of 8 bytes , ptr[0]+1 moves forward size of 4 bytes.

int main() {     int a[] = {1, 2, 3};     int *ptr[3]; //array of 3 elements pointed integer      int *b;      ptr[0] = a;      printf("a: %lu\n", a);     printf("a + 1: %lu\n\n", a+1);      printf("ptr: %lu\n", ptr);     printf("ptr + 1: %lu\n", ptr+1);      printf("ptr[0]: %lu\n", ptr[0]);//ptr[0] holds base address of array     printf("ptr[1]: %lu\n\n", ptr[0] + 1 );      printf("&ptr: %lu\n", &ptr);     printf("&ptr + 1: %lu\n", &ptr+1); }

if understand question correctly, have array of pointers int (int *). expect address of second element 4 bytes higher address of first element, , asking why not so?

if indeed question, answer size of pointer not same size of int.

on 64-bit compiler, size of pointer 8 bytes, while size of int 4 bytes.

you can print out sizeof(int) , sizeof(int *) see clearly.


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