CODEWITHSUNDEEP
javaloopswhile-loopprogram-entry-pointdo-while
user9119361
user9119361

Reputation:

Java - How to end a process of a while function

I need a program that asks the user to introduce up to 10 names (to end, the user could type "fim" [that is end in Portuguese]).

My current problem is how to terminate the program if the user reach 10 names.

Here is my main function: 

public static void main(String[] args) {
    Scanner keyboard = new Scanner (System.in);
    System.out.println("Introduza até 10 nomes completos com até 120 caracteres e pelo menos dois nomes com pelo menos 4 caracteres: ");
    String nome = keyboard.next();
    for(int i = 0; i < 10; i++) {
        while(!nome.equalsIgnoreCase("fim") && i<10) {
            nome = keyboard.next();
        }
    }
    keyboard.close();
}

Upvotes: 0

Views: 63

Answers (3)

Przemysław Moskal
Przemysław Moskal

Reputation: 3609

You might want to give a try to this code (I have made some explanations in the comments to proper lines):

public static void main(String[] args) {
    Scanner keyboard = new Scanner (System.in);
    System.out.println("Introduza até 10 nomes completos com até 120 caracteres e pelo menos dois nomes com pelo menos 4 caracteres: ");
    String nome = keyboard.next();
    int i = 0; // Here I instroduce a counter, to increment it after each input given
    while(!nome.equalsIgnoreCase("fim") && i!=10) { // stop performing while-loop when nome is equal to "fim"
                                                    // or if i==10 (if any of these conditions is false, entire condition is false)
        nome = keyboard.nextLine();
        i++; // increment counter after input
    }
    keyboard.close();
    System.out.println("End of input"); // Just to confirm that you exited while-loop
}

Upvotes: 1

Max Vollmer
Max Vollmer

Reputation: 8598

I am not a big fan of break, so adding to Frakcool's excellent answer, you can use a do-while loop instead:

String nome;
int i = 0;
do {
    nome = keyboard.next();
    i++;
}
while(!nome.equalsIgnoreCase("fim") && i<10);

Also right now you're overwriting all previously entered names. So you either have to handle them directly inside the loop, or collect them in some kind of container, e.g. a list. I would rewrite the loop as such:

String nome;
int i = 0;
while(i<10 && !(nome = keyboard.next()).equalsIgnoreCase("fim")) {
    i++;
    // Either handle nome here directly, or add it to a list for later handling.
}

Upvotes: 2

Frakcool
Frakcool

Reputation: 11143

You're running into an infinite loop with the while as is. You want to change it to an if statement and ask just for fim and call break; if that happens.

So it should end as:

for(int i = 0; i < 10; i++) { //This will run 10 times
    nome = keyboard.next();
    if(nome.equalsIgnoreCase("fim")) { //This will verify if last input was "fim"
        break; //This breaks the for-loop
    }
}

Or if you really want to use a while loop inside the for one (not recommended tho) you need to increase i inside it:

for(int i = 0; i < 10; i++) {
    while(!nome.equalsIgnoreCase("fim") && i<10) {
        nome = keyboard.next();
        i++;
    }
}

Upvotes: 3

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