QBASIC Program to print the area of 4 walls (SUB/FUNCTION Procedure Demo)

CLS
INPUT "Enter Breadth : "; b
INPUT "Enter Height : "; h
area = 2 * h * (l + b)
PRINT "Area of 4 walls = "; area
END

Using SUB Procedure

DECLARE SUB area(l,b,h)
CLS
INPUT "Enter Breadth : "; b
INPUT "Enter Height : "; h
CALL area(l, b, h)
END

SUB area (l, b, h)
     a = 2 * h * (l + b)
     PRINT "Area of 4 walls = "; a
END SUB

Using FUNCTION Procedure

DECLARE FUNCTION area(l,b,h)
CLS
INPUT "Enter Breadth : "; b
INPUT "Enter Height : "; h
a = area(l, b, h)
PRINT "Area of 4 walls = "; a
END

FUNCTION area (l, b, h)
     a = 2 * h * (l + b)
     area = a
END FUNCTION