Chapter 12 Overheads

PROBLEM :	HOW MANY ACCOUNTS DOES EACH CUSTOMER HAVE IN THE DOWN-THE-STREET BANK? A NEW STATE REGULATION SAYS THAT YOUR BANK MUST SUBMIT A REPORT ON HOW MANY ACCOUNTS EACH CUSTOMER HAS. IT IS NOT IMPORTANT WHAT TYPE OF ACCOUNTS THEY ARE; WHAT THEY NEED TO KNOW IS HOW MANY ARE ASSIGNED TO THE SAME SOCIAL SECURITY NUMBER. CAN YOU WRITE A PROGRAM TO TAKE THEIR FILES AND CREATE THE PROPER REPORT?

INPUT :	SOCIAL SECURITY NUMBER (ssno) BALANCE (bal)
OUTPUT :	SOCIAL SECURITY NUMBER NUMBER OF ACCOUNTS (numacts) ACCUMULATED BALANCE (acbal)*

* The govenment doesn't need this, but the bank thinks it would be a useful by-product of the program.

DATA STRUCTURES

	RECORD :	SSNO : ACBAL : NUMACTS :	INTEGER REAL INTEGER
	A ONE DIMENSIONAL ARRAY OF RECORDS

TOP DOWN DESIGN

LEVEL 0:

	WHILE MORE ACCOUNTS
		GET DATA PROCESS DATA
	SORT RECORDS* PRINT RECORDS

* the output must be in order by social security number.

RECORDS :

TYPE ACCOUNT =
	RECORD
		SSNO : ACBAL : NUMACTS :	INTEGER; REAL; INTEGER;
	END;

VAR LIST : ARRAY[1..LIMIT] OF ACCOUNT

LIST[I].SSNO LIST[I].ACBAL LIST[I].NUMACTS

This is like a two dimensional array with the values in each column being a different type.

LEVEL 1:

GET DATA
	READLN( SSNO, BAL )
PROCESS DATA
	IF ACCOUNT NOT ON LIST
		THEN ENTER IT ELSE UPDATE

LEVEL 2:

	NOT ON LIST
		SEARCH LIST FOR CURRENT SSNO BEGINNING AT 1 AND GOING TO CURRENT NUMBER ON LIST IF YOU REACH THE END AND HAVEN'T FOUND IT, THEN ENTER IT AND INCREASE NUMBER ON LIST BY 1 IF FOUND, STOP LOOKING & UPDATE

	UPDATE
		NUMACTS IS WHAT IT WAS + 1 ACBAL IS WHAT IT WAS + BAL

LEVEL 1:

SORT
	FOR COUNTER := 1 TO NUMBER OF ACTS
		FIND MINIMUM BETWEEN COUNTER & NUMBER OF ACTS SWAP MINIMUM & CURRENT
PRINT


PROGRAM BANK( INPUT, OUTPUT );

CONST

   LIMIT = 10000;

TYPE

   ACCOUNT = RECORD

         SSNO : INTEGER;

        ACBAL : REAL;

      NUMACTS : INTEGER

   END;



   ACCOUNTS = ARRAY [1..LIMIT] OF ACCOUNT;



VAR

   LIST : ACCOUNTS;

   NUMCUST : INTEGER


procedures


BEGIN

   PROCESS( LIST, NUMCUST );

   SORT( LIST, NUMCUST );

   PRINT( LIST, NUMCUST );

END.


PROCEDURE PROCESS( VAR LIST : ACCOUNTS; VAR NUMCUST : INTEGER );

VAR

   TEMP : ACCOUNT;

   FOUND : BOOLEAN;

   I : INTEGER;

BEGIN

   NUMCUST := 0;

   REPEAT

      READLN( TEMP.SSNO, TEMP.ACBAL );

      I := 1;

      FOUND := FALSE;

      WHILE NOT FOUND AND (I <= NUMCUST) DO

         IF TEMP.SSNO = LIST[I].SSNO

            THEN FOUND := TRUE

            ELSE I := I + 1;

      IF FOUND THEN

         BEGIN

            LIST[I].ACBAL := LIST[I].ACBAL + TEMP.ACBAL;

            LIST[I].NUMACTS := LIST[I].NUMACTS + 1;

         END

      ELSE

         BEGIN

            TEMP.NUMACTS := 1;

            LIST[I] := TEMP;

            NUMCUST := I;

         END;

   UNTIL EOF;

END;


PROCEDURE SORT( VAR LIST : ACCOUNTS; VAR NUMCUST : INTEGER );

VAR

   I : INTEGER;



(*$ NEST EXCHANGE AND MINI HERE $*)



BEGIN

   FOR I := I TO NUMCUST DO

      EXCHANGE( LIST[I], LIST[MINI( LIST, NUMCUST, I )]);

END;


PROCEDURE EXCHANGE( VAR X, Y : ACCOUNT );

VAR

   TEMP : ACCOUNT;

BEGIN

   TEMP := X;

   X := Y;

   Y := TEMP;

END;



FUNCTION MINI( VAR LIST : ACCOUNTS; NUMCUST, LL : INTEGER ) : INTEGER;

VAR

   I, K : INTEGER;

BEGIN

   K := LL

   FOR I := LL + 1 TO NUMCUST DO

      IF LIST[I].SSNO < LIST[K].SSNO

         THEN K := I;

   MINI := K;

END;


PROCEDURE PRINT( VAR INFO : ACCOUNTS; NUMCUST : INTEGER );

VAR

   I : INTEGER;

BEGIN

   FOR I := 1 TO NUMCUST DO

      WRITELN( INFO[I].SSNO, INFO[I].ACBAL, INFO[I].NUMACTS );

END;

ORDER OF PROGRAM BANK

MAIN PROGRAM declarations

	PROCEDURE PROCESS entire procedure PROCEDURE SORT declarations
		FUNCTION MINI entire function PROCEDURE EXCHANGE entire procedure
	PROCEDURE SORT body PROCEDURE PRINT entire procedure

MAIN PROGRAM body

SUMMARIZE

LINER SEARCH
	WHILE NOT AT LIMIT AND NOT FOUND
RECORDS
	DEFINE :
	TYPE name =	RECORD id1 : TYPE; id2 : TYPE; END;
	VAR id3 : name
	USE : id3.id1 or id3.id2
ORDER OF SUBPROGRAMS
	DEFINE BEFORE FIRST USE