CODEWITHSUNDEEP
pascal
S.Sakthybaalan
S.Sakthybaalan

Reputation: 519

Step value in Pascal programming

I want a programming code to print the odd numbers between a range to teach the students. Here I took the range as 1 to 10. So I want to print the odd numbers between 1 to 10.

I wrote this coding to print the odd numbers between 1 to 10

program printOdd1to10; {Prints odd numbers 1 - 10}

var counter : integer;
begin

   for counter := 1 to 10 do

      begin
        Writeln(counter); {prints new line}
        counter := counter + 2 {increment by value 2, like step 2}
      end;
        Readln;

end.

But when I run, it prints a long series of wrong answer. So, how to print like this pattern odd, even, times of 3(3,6,9...) numbers in pascal programming.

Upvotes: 5

Views: 8699

Answers (4)

chikega
chikega

Reputation: 155

There are Pascal variants that support step values for looping constructs. One is PascalABC.Net which is open source and is extensively used for teaching. The other is a commercial product, REMObjects Oxygene. Both allow the declaration of in-line variables.

Oxygene:

namespace ForLoopStep_Oxy;

begin
  for counter := 1 to 10 step 2   
    writeLn(counter);   // 1 3 5 7 9 
    
  for counter := 9 downto 0 step 2  
    writeLn(counter);   // 9 7 5 3 1
end.

PascalABC.Net:

begin
  for var i := 1 to 10 step 2 do
    Writeln(i);   // 1 3 5 7 9
  Writeln;
  
  for var j := 9 to 0 step -2 do
    Writeln(j);  // 9 7 5 3 1
  Writeln;
  
  for var k :='z' to 'a' step -2 do
    Write(k);   // zxvtrpnljhfdb
  Writeln;
end.

Upvotes: 0

No'am Newman
No'am Newman

Reputation: 6477

Following Jeff's answer, the best way to code your program is with 'while'.

i:= 1;  // start with an odd number
while i < 10 do
 begin
  writeln (i);
  i:= i + 2;  // or inc (i, 2)
 end;

Incrementing i by 2 each time will ensure that i is always odd, so there's no need to check this.

Upvotes: 6

la-la
la-la

Reputation: 31

I am not so familiar with pascal. But, I have a suggestion for you, what about using conditional to check the number if it divides into 2 with remaining of 1 (Like 5/2 and the remaining is 1) and then print it.

I hope it will help you.

Upvotes: 1

Jeff Zeitlin
Jeff Zeitlin

Reputation: 10799

The for statement in Pascal does not support a step value, and you shouldn't alter the value of the index variable (this is a general principle for programming). Either test the index variable's value for the condition you are interested in (e.g., if odd(counter) then...), or re-code as a while or repeat...until loop, where you can have a 'pseudo-index' variable that you can manipulate as you feel necessary.

Upvotes: 4

Related Questions