Pointer variable p begins to store the value to the address it points to without allocating storage space, which is of course wrong.

int * p =(int *)malloc(256 * sizeof(int))； //Let him point to a dynamically allocated memory block.

or

int a[256]= { 0 }；

int i，* p；

p = a；

for(I = 0； I & lt256; i++)

{

*(p+I)= I；

}

It's okay, let p point to an array a.

Only one int can be stored in dynamically allocated memory.

p =(int *)malloc(sizeof(int))；

change into

p =(int *)malloc(sizeof(int)* 256)；