So, pr is a pointer to struct rectangle. So now, how would you pass the argument, you would say address of the rectangle r. So, you would say area and the parameter is address of r.
आपल्याला फंक्शन ला अर्ग्युमेण्ट म्हणून पास करायचे असेल तर ऍड्रेस ऑफ rect r. आणि आताच बघितल्या प्रमाणे struct rect *pr.