The most common loop in Pascal is the FOR loop. The statement inside the for block is executed a number of times depending on the control condition. The format's for the FOR command is,

	FOR var_name := initial_value TO final_value DO  program_statement;

	FOR var_name := initial_value TO final_value DO

	begin

	    program_statement; {to execute more than one statement in a for }

	    program_statement; {loop, you group them using the begin and    }

	    program_statement  {end statements                              }

	end;                   {semi-colon here depends upon next keyword   }
	FOR var_name := initial_value DOWNTO final_value DO  program_statement;

You must not change the value of the control variable (var_name) inside the loop. The following program illustrates the for statement.

	program  CELCIUS_TABLE ( output );

	var      celcius : integer; farenhiet : real;

	begin

	         writeln('Degree''s Celcius   Degree''s Farenhiet');

	         for  celcius := 1  to  20  do

	         begin

	             farenhiet := ( 9 / 5 ) * celcius + 32;

	             writeln( celcius:8, '      ',farenhiet:16:2 )

	         end

	end.

CLASS EXERCISE
What is the resultant output when this program is run.

	program  FOR_TEST ( output );

	var      s, j, k, i, l : integer;

	begin

	         s := 0;

	         for  j:= 1 to 5 do

	         begin

	             write( j );

	             s := s + j

	         end;

	         writeln( s );

	         for  k := 0 to 1 do write( k );

	         for  i := 10 downto 1 do writeln( i );

	         j := 3; k := 8; l := 2;

	         for  i := j to k do  writeln( i + l )

	end.

Class Exercise .. Output of program FOR_TEST is,

	1234515

	0110

	9

	8

	7

	6

	5

	4

	3

	2

	1

	5

	6

	7

	8

	9

	10

---------------

For the first twenty values of farenhiet, print out the equivalent degree in celcuis (Use a tabular format, with appropiate headings). [C = ( 5 / 9 ) * Farenhiet - 32] 
Use the statement writeln('<14>'); to clear the screen. 


PROGRAM NINE  Table of 1 to 20 Celcius

program PROG9 (output);

var   farenhiet : real;

      celcius   : integer;

begin

    writeln('<14>');     {clear screen on DG machine}

    writeln('Degree''s Celcius   Degree''s Farenhiet');

    for celcius := 1 to 20 do

    begin

       farenhiet := ( 9 / 5 ) * celcius + 32;

       writeln( celcius:8, '      ', farenhiet:16:2 )

    end

end.