Loop problem (while)

Hello,

I post again on this Fourm because I have a problem with the while and or place
his braces. The following program works if I enter a single number, but I want to
execute this piece of code until the user enters -1 (I do it so it does not appear in the following code):

Code:

---

    if (nombreEntre > 0 && nombreEntre <= 1000000)
 
        {
            compteurNombres++;
            additionNombres = nombreEntre;
        }
 
        if (nombreEntre < 2) // Si le nombre entré est plus petit que 2
        {
            premier = false;
        }
 
        while (compteurNombrePremier * compteurNombrePremier <= nombreEntre)
        {
 
            if (nombreEntre % compteurNombrePremier == 0)
            /* Si le résultat de l'un des modulos des nombres testés = 0,
            alors il est composé */
            {
                premier = false;
            }
            compteurNombrePremier = compteurNombrePremier + 1;
        }
 
        if (premier) // Si le nombre est premier
        {
            System.out.println(nombreEntre + " est un nombre premier");
        }
        else // Si le nombre n'est pas premier
        {
            System.out.println(nombreEntre + " n'est pas un nombre premier");
        }
 
        while (nombreEntre >= racineCarree * 2 + 1)
        {
            nombreEntre -= (racineCarree * 2 + 1);
            racineCarree++;
        }
 
 
        if (racineCarree * racineCarree != nombreEntre)
        /* Si le carré de la racine n'égale pas le nombre entré,
        alors elle est approximative */
        {
            System.out.println("La racine entière approximative est"
                    + " " + racineCarree);
            racineApprox++;
            // Le nombre de racines approximatives trouvées augmente de 1
            compteurRacines++;
        }
        else
        {
            System.out.println("La racine entière exacte est " + racineCarree);
            /* Si le carré de la racine égale au nombre entré, alors elle est
            exacte */
            racineExacte++; /* Le nombre de racines exactes trouvées
            augmente de 1 */
            compteurRacines++; // Le nombre de racines trouvées augmente de 1
        }

---

I really do not know where to place it. I have tried many times, but still the same result: It gets stuck in an infinite loop.

Thank you for your help

Quote:

---

Originally Posted by roud9

I have tried many times, but still the same result: It gets stuck in an infinite loop.

---

bonjour. in order to stop the loop you need somewhere to get the input of the user and then decide whether to continue or break.

I had added this at the begenning :

Code:

---

        if (nombreEntre > 0 && nombreEntre <= 1000000)
        {
 
            compteurNombres++;
            additionNombres = nombreEntre;
            while (nombreEntre > 0 && nombreEntre <= 1000000)
            {
                System.out.println("Entrez le nombre dont vous voulez" + " extraire la racine carrée ");
                nombreEntre = Integer.parseInt(r.readLine());
            }
        }

---

but it gets stuck in the loop and always ask me a number

What happens if you enter zero or a negative number or a number bigger than one million?

It stops the program but I want if number < -1 and > 1000000 it will ask me enter a other number

Do you see how the conditions being tested in your loop control when you exit the loop?
When do you want to exit the loop and
when do you want to stay in the loop?

now it works when I enter numbers between 0 and one million. But the first time, it gave me a good result, the second time or after, it gave me a wrong result

Can you explain what a wrong result is?

For exemple I enter 3 : prime number and sqrt without decimal gave me 1 // Correct
The second time it askimg me a number, I enter 9: not prime and sqrt = 3 // Correct
But the third time I re-enter 3 : not prime and sqrt = 3...
I don't understand why it give me this and it's for all numbers

Why does it work differently the second time you enter a 3 from the first time you enter a 3?
Should the program give the same answer every time you enter a 3?

This looks like a logic problem with your program.
You need to play computer. Take a piece of paper and step through the logic step by step writing down the values of the variables as they change until you see where your logic is wrong.
Or you could add print out statements to your code to show how variables change as the program executes and to show how the execution flow goes.

Thanks I found the problem :D