Limit number of input lines in Java?

Question

I have a problem where I want to take input from the user, the user can insert 1 and up to 8 lines, and each line represents a case. What I want is to stop the scanner when the user inserts 8 lines, Or if the user wants less than 8 he can press enter or a specific key to end the loop.

What I have done so far:

public static void doSomthing(){

    Scanner input = new Scanner(System.in);

    while (input.hasNextLine()) { // here I want to check so that it don't exeed 8 lines
        int e;
        int m;
        i = input.nextInt();
        j = input.nextInt();

        int num = 0;


        while (i != 0 || j != 0) {
            num += 1;
            e = (e + 1) % 100;
            m = (m + 1) % 400;
        }

        System.out.println(num);
    }

}

The input should be two numbers in each line, one for i and one for j.

Input:

0 0
100 300
99 399
0 200

Output should be:

C1: 0 
C2: 100
C3: 1
C4: 200

Hope this explains my problem.

Thanks in advance!

Answer 1

As @Abhishek suggested, you can use a counter variable:

public static void doSomthing(){
    Scanner input = new Scanner(System.in);
    int linesParsed = 0;
    while (linesParsed < 8 && input.hasNextLine()) {
        // What are you using these variables for? You compute their
        //  values, but then you do not use them
        int e;
        int m;
       // Where are these variables declared? It seems weird to have
        //  instance variables be named i and j
        i = input.nextInt();
        j = input.nextInt();

        int num = 0;
       
        // Unless i and j are being modified concurrently somewhere
        // else in the code, this will result in an infinite loop
        while (i != 0 || j != 0) {
            num += 1;
            e = (e + 1) % 100;
            m = (m + 1) % 400;
        }

        System.out.println(num);
        linesParsed++;
    }
}