How do I recursively count up to less than n [closed]

I am struggling with the problem of having applications of loops and arrays.

I have a variable “n” which represents the limit of the loop, i.e.

if n = 3, the array would look like:

arr[1,2,3,1,2,3,1,2,3];

or if n = 4, it would look like:

arr[1,2,3,4,1,2,3,4,1,2,3,4,1,2,3,4];

here’s my code so far, someone please let me know the mistake I have made in implementing the above problem…

public static void main(String[] args) {
    
    countingUp(3);

}

public static void countingUp(int n) {
    int[] arr = new int[n * n];
    int k = n;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            arr[i] = n ;
        }
    }
    
    System.out.println(Arrays.toString(arr));
}

Answer

This is the major mistake you have done…

arr[i] = n ;

You should update value after each interval of length n which can be controlled by the loop running with i and the value inside each interval could be controlled with the loop j. See that one change I have made in the code below…

public static void main(String[] args) {
    
    countingUp(3);

}

public static void countingUp(int n) {
    int[] arr = new int[n * n];
    int k = n;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            arr[i*n+j] = j+1 ;
        }
    }
    
    System.out.println(Arrays.toString(arr));
}