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jayshaw94

Fri Apr 08, 2011 10:51 am


loop help please

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Hello compsci once again i come with another problem
I am having trouble using a loop statement.

Here is the problem. If the user enters a number that is greather than 2 a message will come up stating "Error please try again". I have that message working but it won't exit the loop if the number is less than equal or less than 2. I tried if statements aswell with no luck. Any help would be great. I bolded the the area i am having issues with

var h1, h2, h3, w1, w2, w3, choice, HOF1, HOF2, WOF1 : int
var RailA := 46
var RailB := 41

procedure Form1
    if choice = 1 then
        HOF1 := (h1) - (RailA)
        put "Height of frame = ", HOF1, " Width of Frame ", w1
    else
        HOF2 := (h1) - (RailB)
        put "Height of Frame = ", HOF2, " Width of Frame ", w1
    end if
end Form1
procedure RailChoice
    put "Rail A (1)Set on the Floor"
    put "Rail B (2)Set into the Floor"
    get choice
    loop
        if choice > 2 then
            put "Error please try again"
            RailChoice
        end if
    end loop
end RailChoice
procedure hwconfig
    put "Enter lowest room height"
    get h1
    put "Enter second lowest room height"
    get h2
    put "Enter third lowest room height"
    get h3
    put "Enter lowest room width"
    get w1
    put "Enter second lowest room width"
    get w2
    put "Enter third lowest room widht"
    get w3
    if (h1) - (h2) > 12 then
        put "Exceeds 12mm limit Rail B is the default"
    elsif (h2) - (h3) > 12 then
        put "Exceeds 12mm limit Rail B is the default"
    elsif (h3) - (h1) > 12 then
        put "Exceeds 12mm limit Rail B is the default"
    elsif (h1) - (h3) > 12 then
        put "Exceeds 12mm limit Rail B is the default"
    end if
end hwconfig


RailChoice
hwconfig
Form1


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goroyoshi

Fri Apr 08, 2011 11:01 am


RE:loop help please

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try using "exit when"


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jayshaw94

Fri Apr 08, 2011 11:16 am


RE:loop help please

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thanks  tried exit when before it wasnt working but i tried again i guess i was initially doing it wrong
thanks!


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Insectoid

Fri Apr 08, 2011 11:19 am


RE:loop help please

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Not related to your question, but

[code]
f (h1) - (h2) > 12 then 
put "Exceeds 12mm limit Rail B is the default" 
elsif (h2) - (h3) > 12 then 
put "Exceeds 12mm limit Rail B is the default" 
elsif (h3) - (h1) > 12 then 
put "Exceeds 12mm limit Rail B is the default" 
elsif (h1) - (h3) > 12 then 
put "Exceeds 12mm limit Rail B is the default" 
end if 
[/code]

This can be cleaned up, a LOT. 

Note that this will *always* fail (you'll always get the message 'Exceeds 12mm limit....').


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Raknarg

Fri Apr 08, 2011 3:18 pm


RE:loop help please

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You have a few problems here.


procedure RailChoice 
   put "Rail A (1)Set on the Floor" 
   put "Rail B (2)Set into the Floor" 
   get choice 
   loop 
      if choice > 2 then 
         put "Error please try again" 
         RailChoice 
      end if 
   end loop 
end RailChoice 



First of all, there's no exit statement. So if your answer is less than 3, it will loop for all eternity.
Then you seem to try and fix it with recursion. All this will do is call itself inside itself, like this:


procedure
    do stuff
    calls procedure
         do stuff
         calls procedure
              do stuff
              calls procedure

 
and so on. It also creates an infinite loop, but of endless procedures. What you need to do is put everything inside the procedure in the SAME loop, and use an exit statement. And do not call itself, it's unnescessary with what you're doing.


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TokenHerbz

Fri Apr 08, 2011 7:19 pm


RE:loop help please

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i just want to point out, if there is no "loop" then theres no required "exit" for that.

One could think of it as a "call word" get word "if word = this -> then that -> else go onwards.  you could also include the recursion setup into this.

proc test
      get "tester"
      if tester < 2 then
           test %again
      end if
      %got test and do test etc,
end test
^^the above isn't tested but would work :P