2d Array in Spiral Order

Question

I\'m trying to fill an array in spiral order. So far, I can print the array in spiral order, but is there a way to modify the array so that i can fill it in spiral order and

Answer 1

Below function is a square matrix with a size N × N containing integers from 1 to N * N in a spiral order, starting from top-left and in clockwise direction.

int[][] spiralNumbers(int n) {
int[][] matrix = new int[n][n];
for (int step = 0, a = 0, size; step < n/2; step++) {
    size = (n - step * 2 - 1);
    for (int i = 0, chunk, chunkIndex, chunkOffset; i < 4 * size; i++) {
        chunk = i / size;
        chunkIndex = i % size;
        chunkOffset = n - step - 1;
        switch (chunk) {
            case 0:
                matrix[step][chunkIndex + step] = a+1;
                break;
            case 1:
                matrix[chunkIndex + step][chunkOffset] = a+1;
                break;
            case 2:
                matrix[chunkOffset][chunkOffset - chunkIndex] = a+1;
                break;
            case 3:
                matrix[chunkOffset - chunkIndex][step] = a+1;
                break;
            default:
                throw new IndexOutOfBoundsException();
        }
        a++;
    }
    if (n % 2 == 1) {
        matrix[n/2][n/2] = n * n;
    }
}
return matrix; 
}