Negatives

[AK.E]

I have a program in which I want to get a number but prevent them from entering negatives. I know I can simply use if number < 0 then... but that only works for the first time. Let's say someone enters -5.. it won't except it.. but when they enter 100 then -5 it will because the number will be 95 which is above 0.

Here's my code:

Turing:

var numberOfBars : string var numberOfBarsInt : int var barX : int := 0 get numberOfBars                                          if strintok (numberOfBars) then                    numberOfBarsInt := strint (numberOfBars) + barX                  put numberOfBarsInt                                      else             put " "             put "Please insert a valid integer."

[Clayton]

use natural numbers instead of integers

Turing:

var my_nat : nat := 5

[Cervantes]

There are strnat and strnatok functions, yes? Using those would solve your problem.