Advanced Pascal Programming Language Problems
© 1998 by Dr. Thomas W. MacFarland -- All Rights Reserved
Instructions: Review the following program and see if you can predict the outcome by completing a "pencil trace" of the code. Program output is provided at the end of this page. Compiler: The program was prepared using Standard Pascal on a UNIX-based host computer.
% cat PASCAL/advanced_pencil-11.p
{ Advanced Pascal Programming Language Exercises
Dr. Thomas W. MacFarland
advanced_pencil-11.p
}
{ The purpose of this program is to:
1. Demonstrate the use of an array of integers.
2. Demonstrate the printing of individual elements of
an array.
3. Demonstrate the difference between a variable value
and the value of an array element.
}
program Demonstrate_Arrays_2;
var A : array[1..20] of integer;
B : integer;
begin
B := 100;
A[B] := B + 3;
writeln('B = ',B:10);
writeln('**************');
for B := 1 to 21 do
writeln('B = ', B:10);
end. {advanced_pencil-11.p}
% pc PASCAL/advanced_pencil-11.p
% a.out
B = 100
**************
B = 1
B = 2
B = 3
B = 4
B = 5
B = 6
B = 7
B = 8
B = 9
B = 10
B = 11
B = 12
B = 13
B = 14
B = 15
B = 16
B = 17
B = 18
B = 19
B = 20
B = 21