squareMatrix_to_spiral_sequence(MoreReadable).c

#include<stdio.h>
int main() {
    int i, j, array[99][99], n, tmp, directionI = 1, directionJ = 1, flip = 0, length;

    printf("Enter n of a square matrix: ");
    scanf("%d", &n);
    tmp = length = n;

    printf("\n");
    for (i = 0; i < n; i++)
        for (j = 0; j < n; j++)
            array[i][j] = i * n + j + 1;

    for (i = 0; i < n; i++) {
        for (j = 0; j < n; j++)
            printf("%d\t", array[i][j]);
        printf("\n");
    }

    printf("\nsequence: ");
    for (i = j = 0; length; --tmp ? 0 : (directionI *= 1 - 2 * flip, directionJ *= 2 * flip - 1, tmp = length -= flip = !flip), i += directionI * flip, j += directionJ * !flip)
        printf("%d,", array[i][j]);
    return 0;
}