与C中的数组大小混淆

Question

Why does the sizeof (array [0]) return size as 8 when it has 17 characters/bytes within it?

#include <stdlib.h>
#include <stdio.h> 

int main  () {

  char* array [2] = {"12345678912345678","12345678"};
  int a = sizeof  (array [0]);

  fprintf (stdout, "%s , %d \n", array [0], a);

  return 0;
}

Returns:

12345678912345678 , 12345678

Answer 1

To get the length of the actual character string being stored, use

printf("%lu", strlen(array[0]));

This gives 17 .

Make sure to include the <string.h> header.

Answer 2

sizeof(array [0]) returns the size of the pointer which is depend your system. Use strlen() function to get your expected output.

  int a = strlen(array [0]);