Need help for outputing prime number

[Johnny19931993]

I'm trying to make a program that calculates all the prime numbers from 1 to 50
but i don't know why my program didn't output anything
can anyone help me?

Turing:

const QUANTITY := 50 var number : array 1 .. QUANTITY of int var counter := 0 for x : 1 .. QUANTITY     number (x) := x     for y : 1 .. x         if number (x) mod y = 0 then             counter += 1         end if     end for     if counter = 2 then         put number (x)     end if end for

[cavetroll]

Your problem is you need to reset the counter for every loop through. Try something like:

Turing:

const QUANTITY := 50 var number : array 1 .. QUANTITY of int var counter := 0 for x : 1 .. QUANTITY     counter := 0     number (x) := x     for y : 1 .. x         if number (x) mod y = 0 then             counter += 1         end if     end for     if counter = 2 then         put number (x)     end if end for

[DanielG]

your mistake is going from 1 .. x, it should be 1.. x-1, also, make sure you don't check one, since it is NOT a prime but will be shown as one by the formula you have written

[Johnny19931993]

DanielG @ Tue Feb 03, 2009 5:33 pm wrote:

your mistake is going from 1 .. x, it should be 1.. x-1, also, make sure you don't check one, since it is NOT a prime but will be shown as one by the formula you have written

even though my problem is already solved by the help of cavetroll, I still want to point out that the program will not output 1 whatsoever
because if i put

Turing:

for x : 1..1

the loop will only go once, therefore, it is impossible for the value of "counter" to be 2
so if "number" is equal to 1, the program will not output 1

[andrew.]

Why don't you make it like if the number is 1, then put 1, if it's anything else, then go into your for loop.