Loops/Downward for: Difference between revisions

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WRITE(*, *) i
WRITE(*, *) i
END DO
END DO

=={{header|J}}==
J is array-oriented, so there is very little need for loops. For example, one could satisfy this task this way:

,. i. -11

J does support loops for those times they can't be avoided (just like many languages support gotos for those time they can't be avoided).
<pre>
3 : 0 ] 11
for_i. i. - y do.
i 1!:2 ]2
end.
i.0 0
)
</pre>

Though it's rare to see J code like this.



=={{header|Java}}==
=={{header|Java}}==

Revision as of 19:06, 2 August 2008

Task
Loops/Downward for
You are encouraged to solve this task according to the task description, using any language you may know.

Write a for loop which writes a countdown from 10 to 0.

Ada

<ada> for I in reverse 0..10 loop

  Put_Line(Integer'Image(I));

end loop; </ada>

C++

<cpp> for(int i = 10; i >= 0; --i)

 std::cout << i << "\n";

</cpp>

ColdFusion

With tags:

<cfloop index = "i" from = "10" to = "0" step = "-1">
  #i#
</cfloop>

With script:

<cfscript>
  for( i = 10; i <= 0; i-- )
  {
    writeOutput( i );
  }
</cfscript>

D

<d>for(int i = 10; i >= 0; --i) writefln(i)</d> Foreach Range Statement since D2.003 <d>foreach_reverse(i ; 0..10+1) writefln(i) ;</d>

Forth

Unlike the incrementing 10 0 DO-LOOP, this will print eleven numbers. The LOOP words detect crossing the floor of the end limit.

: loop-down  0 10 do  i .  -1 +loop ;

Fortran

Works with: Fortran version 90 and later
DO i = 10, 0, -1
  WRITE(*, *) i
END DO

J

J is array-oriented, so there is very little need for loops. For example, one could satisfy this task this way:

  ,. i. -11

J does support loops for those times they can't be avoided (just like many languages support gotos for those time they can't be avoided).

   3 : 0 ] 11
        for_i. i. - y do.
            i 1!:2 ]2 
        end.
     i.0 0
   )

Though it's rare to see J code like this.


Java

<java>for(i = 10; i >= 0; --i){

  System.out.println(i);

}</java>

JavaScript

<javascript>for (var i=10; i>=0; --i) print(i);</javascript>

If the limit is less than the start, then FOR decrements the control variable. Otherwise, a fourth parameter could be given as a custom increment.

for [i 10 0] [print :i]

MAXScript

for i in 10 to 0 by -1 do print i

OCaml

<ocaml>for i = 10 downto 0 do

 Printf.printf "%d\n" i

done</ocaml>

Pascal

<pascal> for i := 10 downto 0 do

 writeln(i);

</pascal>

Perl

<perl>foreach (reverse 0..10) {

 print "$_\n";

}</perl>

Pop11

lvars i;
for i from 10 by -1 to 0 do
   printf(i, '%p\n');
endfor;

Python

<python> for i in xrange(10, -1, -1):

   print i

</python>

UnixPipes

yes \ |cat -n |head -n 10 | tac