Chapter 4 Overheads

Problem

What letter grade did I make in my history class given the following grading scheme:

2	Exams (maximum of 50 points on each), drop the lower grade

1	Final exam (maximum of 50 points)

100 is total possible points

Number Grade
90+
80 - 89
67 - 69
55 - 66
below 55

Letter Grade
A
B
C
D
F

Understand the Problem?

TOP DOWN DESIGN:

	INPUT:	THREE GRADES (exam1, exam2, final)
	OUTPUT:	A LETTER GRADE

LEVEL 0:

GET GRADES
COMPUTE NUMERIC GRADE (numgrade)
ASSIGN LETTER GRADE (letgrade)
PRINT LETTER GRADE

LEVEL 1:

GET GRADES

READ( exam1, exam2, final )

COMPUTE NUMERIC GRADE

GET MAXIMUM EXAM GRADE
ADD FINAL GRADE

ASSIGN LETTER GRADE

numgrade in 90 or better,
THEN letgrade is A.

numgrade is between 80 and 89,
THEN letgrade is B.

numgrade in between 67 and 79,
THEN letgrade is C.

numgrade in between 55 and 66,
THEN letgrade is D.

numgrade in less than 55,
THEN letgrade is F.

PRINT LETTER GRADE

LEVEL 2:

GET MAXIMUM EXAM GRADE
	IF	exam1 is greater than exam2, THEN maximum is exam1
	OTHERWISE maximum is exam2
ADD FINAL GRADE
	numgrade is maximum + final

CONTROL STRUCTURE

	IF (logical exp. is true)
		THEN statement1 ELSE statement2

PROGRAM GRADE(INPUT,OUTPUT);



VAR


  
  EXAM1, EXAM2, FINAL, NUMGRADE : INTEGER;

      LETGRADE : CHAR;
  




BEGIN


  
  READ(EXAM1,EXAM2,FINAL);

  
  IF EXAM1 >= EXAM2

  
  
  THEN NUMGRADE := EXAM1 + FINAL

                ELSE NUMGRADE := EXAM2 + FINAL;
  

  
  IF NUMGRADE >= 90 THEN LETGRADE := 'A'

                ELSE IF NUMGRADE >= 80 THEN LETGRADE := 'B'
  

  
  
  ELSE IF NUMGRADE >= 67 THEN LETGRADE := 'C'

  
  
  
  ELSE IF NUMGRADE >= 55 

  
  
  
  
  THEN LETGRADE := 'D'

            ELSE LETGRADE := 'F'
  

  
  WRITELN('YOUR GRADE IS ', LETGRADE)


END.

ALTERNATE TOP DOWN DESIGN

LEVEL 0:

GET GRADES
COMPUTE NUMERIC GRADE
PRINT LETTER GRADE

LEVEL 1:

IF NUMGRADE >= 90 THEN WRITE(' A') ELSE IF NUMGRADE >= 80 THEN WRITE(' B')
	ELSE IF NUMGRADE >= 67 THEN WRITE(' C')
		ELSE IF NUMGRADE >= 55
			THEN WRITE(' D') ELSE WRITE(' F')

SUMMARIZE

PHYSICAL ORDER
LOGICAL ORDER
	BOOLEAN EXPRESSION
		TRUE
		FALSE
	IDENTIFIER		< > <= >= = not =	IDENTIFIER
IF BOOLEAN EXPRESSION
	THEN statement1
	ELSE statement2
TYPE: INTEGER & CHAR

`READ(EXAM1,EXAM2,FINAL);`
`IF EXAM1 >= EXAM2`
	`THEN NUMGRADE := EXAM1 + FINAL ELSE NUMGRADE := EXAM2 + FINAL;`
`IF NUMGRADE >= 90 THEN LETGRADE := 'A' ELSE IF NUMGRADE >= 80 THEN LETGRADE := 'B'`
	`ELSE IF NUMGRADE >= 67 THEN LETGRADE := 'C'`
		`ELSE IF NUMGRADE >= 55`
			`THEN LETGRADE := 'D' ELSE LETGRADE := 'F'`
`WRITELN('YOUR GRADE IS ', LETGRADE)`