#include <stdio.h>
#include <math.h>

struct point
{
    int xpos;
    int ypos;
};

int main()
{
    struct point pos1={1, 2};
    struct point pos2={100, 200};
    struct point * pptr=&pos1;

    (*pptr).xpos +=4;
    (*pptr).ypos +=5;
    printf("[%d, %d] \n", pptr->xpos, pptr->ypos);

    pptr=&pos2;
    pptr->xpos +=1;
    pptr->ypos +=2;
    printf("[%d, %d] \n", (*pptr).xpos, (*pptr).ypos);

    return 0;
}