public class Boxes {

   class Point {
      int x;
      int y;
   }

   class Rect {
      Point pt1;
      Point pt2;
   }

   public void makeBox() {
      Rect box = new Rect();

      box.pt1 = new Point();

      box.pt2 = new Point();

      box.pt1.x = 3;
      box.pt1.y = 2;
      box.pt2.x = 11;
      box.pt2.y = 7;
      System.out.println(
         "width: " + width(box) +
         ", height: " + height(box));
   }

   int width(Rect r) {
      return Math.abs(r.pt1.x - r.pt2.x);
   }

   int height(Rect r) {
      return Math.abs(r.pt1.y - r.pt2.y);
   }
   public static void main(String[] args) {
      Boxes b = new Boxes();
      b.makeBox();
   }
}

#include <stdio.h>

struct point {
   int x;
   int y;
};

struct rect {
   struct point *pt1;
   struct point *pt2;
};

void makebox() {
   struct rect *box = 
      (struct rect *)malloc(sizeof(struct rect));
   box -> pt1 =
      (struct point *)malloc(sizeof(struct point));
   box -> pt2 =
      (struct point *)malloc(sizeof(struct point));
   box -> pt1 -> x = 3;
   box -> pt1 -> y = 2;
   box -> pt2 -> x = 11;
   box -> pt2 -> y = 7;
   printf("width: %i, height: %i\n",
      width(box), height(box));
}

int width(struct rect *r) {
   return abs(r -> pt1 -> x - r -> pt2 -> x);
}

int height(struct rect *r) {
   return abs(r -> pt1 -> y - r -> pt2 -> y);
}

int main() {
   makebox();
}

% cc -o boxes boxes.c
% boxes
width: 8, height: 5

% javac Boxes.java
% java Boxes
width: 8, height: 5