the following structures are designed to store information about objects on a graphics screen. a point structure stores the x and y coordinates of a point on the screen. a rect structure stores the coordinates of the upper left and lower right corners of a rectangle. struct point { int x, int y;}; struct rect { struct point upperleft, lowerright; }; 1) write functions that perform the following operations on a rect structure r passed as an argument: (a) compute the center of r, returning it as point value. function name: center (b) move r by x units in the x direction and y units in the y direction, returning the modified version of r. (x and y are additional arguments to the function.) function name: move 2) suppose following declaration is in effect. struct rect *p; assume that
