sizeof () different when the pointer and array are evaluated

sizeof () takes the size of the number of bytes in memory of the parameter.

sizeof in the pointer and array of the need to pay attention to the place;

#include <stdio.h>

int main ()

{

char *p = NULL;

Char arr[10];

Char str[]= "Hello";

int A, B, D, E, F, g,h;

A = sizeof (*P);//pointer type. A=1;

b = sizeof (p);//sizeof asks any pointer to be 4 bytes. b=4;

d = sizeof (arr);//space occupied by array elements;d=10;

E = sizeof (arr[10]);//The space size of the 10th element. e=1;

f = sizeof (&arr);//sizeof it as an address, 4 bytes f=4;

g = sizeof (&arr[10]);//And above the same g=4;
H=sizeof (str);//The string length is included in the last "" ", so it is 6 characters h=6;

printf ("%d%d%d%d%d%d%d", A, B, D, E, F, g,h);

}

Result A=1;b=4;d=10;e=1;f=4;g=4;h=6

sizeof () is different when the pointer and array are evaluated