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\line{\sevenrm a102.tex[106,phy] \today\hfill}

\font\rmn=amr9

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\line{(Assumes conditionals, assignment)\hfil}

{\rmn
{\narrower\smallskip\noindent
{\bf Exercise:} ({\tt DIV} and {\tt MOD}) (or use as example?)

A bank represents the amounts of accounts, checks, deposits, etc., by integers,
using cents rather than dollars within the computer program. Design a procedure
to print such integers as dollar amounts in legible form; for example,
12345678 would be printed as \$123,456.78, and 12 would be printed as \$0.12.
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}

{\rmn
{\narrower\smallskip\noindent
{\bf Solution.}
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}

\smallskip
{\obeylines\obeyspaces\let =\ \tt
        PROCEDURE DOLLARPRINT(CENTS:INTEGER);
        VAR COUNT, POSITION, I: INTEGER;
\smallskip
        BEGIN
        COUNT:=3; POSITION:=100;
\smallskip
        WHILE CENTS>=10*POSITION DO
           BEGIN
           POSITION:=10*POSITION;
           COUNT:=COUNT +1
           END;
        WRITE ('\$');
        FOR I:=COUNT DOWNTO 1 DO
           BEGIN
           WRITE(CENTS DIV POSITION:1);
           CENTS:=CENTS MOD POSITION;
           POSITION:=POSITION DIV 10;
           IF I=3 THEN WRITE ('.')
           ELSE IF I MOD 3=0 THEN WRITE (',')
           END
        END;
}

\smallskip
{\rmn
{\narrower\smallskip\noindent
The first half of this program, {\tt POSITION} is set to the place value
of the first decimal digit needed, and {\tt COUNT} is the number of digits
needed. The program may fail by {\tt 10*POSITION} exceeding {\tt MAXINT}.
\smallskip}
}


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\line{\copyright 1984 Robert W. Floyd; 
First draft (not published) May 16, 1984\hfil}
%revised: Date; subsequently revised.\hfill}

\bye