import java.util.Scanner;

public class Example {
    public static void main(String[] args) {
        Scanner reader = new Scanner(System.in);
        System.out.print("Give a number: ");
        int num = Integer.valueOf(reader.nextLine());

        int counter = 1;
        while (counter <= num) {
            System.out.println(counter);
            counter++; // increases the value with one
        }
    }
}


Give a number: 5
1
2
3
4
5



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import java.util.Scanner;

public class Example {
    public static void main(String[] args) {
        Scanner reader = new Scanner(System.in);
        
        while (true) {
            System.out.print("Give a number: ");
            int num = Integer.valueOf(reader.nextLine());

            if (num == 0) {
                break;
            }

            System.out.println("The square of the number is" + (num * num));
        }
        System.out.println("Hi!");
    }
}

Give a number: 2
The square of the number is 4
Give a number: 4
The square of the number is 16
Give a number: 6
The square of the number is 36
Give a number: 5
The square of the number is 25
Give a number: 0
Hi!