13
Pointer
#include <stdio.h>
int main(void) {
    int a;
    int* pa;
    scanf("%d",&a);
    printf("a=%d\n",a);
    pa=&a;
    scanf("%d",pa);
    printf("a=%d\n",a);
    *pa=12345;
    printf("a=%d\n",a);
    return 0;
}