Nom nom

#include <stdio.h>
#include <stdlib.h>

/*
N = 5
    5       6       7       8       9
    4       19      18      17      10
    3       20      25      16      11
    2       21      24      15      12
    1       22      23      14      13

N = 7
    7       8       9       10      11      12      13
    6       29      28      27      26      25      14
    5       30      39      40      41      24      15
    4       31      38      49      42      23      16
    3       32      37      48      43      22      17
    2       33      36      47      44      21      18
    1       34      35      46      45      20      19
*/

void printm(int *matriks, int n)
{
    int i, j;

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

    printf("\n\n");
}

int main()
{
    int n, i, j, k, dim, count, geser, batas;
    int *matriks;

    printf("Input: ");
    scanf("%d", &n);

    matriks = malloc(n*n*sizeof(int));

    for (i=0; i<n; i++)
    {
        for (j=0; j<n; j++)
        {
            matriks[i*n + j] = 0;
        }
    }

    i     = n-1;
    j     = 0;
    dim   = n/2;
    geser = 1;
    batas = n;
    count = 0;

    printf("Output:\n");

    for (k=0; k<dim; k++)
    {
        for (; i >= k; i--) {
            matriks[i*n + j] = ++count;
        }
        i++;
        for (j += geser; j != batas; j += geser) {
            matriks[i*n + j] = ++count;
        }
        j -= geser;
        for (i++; i < n; i++) {
            matriks[i*n + j] = ++count;
        }
        i--;

        if (k%2==0) {
            geser = -1;
            batas = k;
            j--;
        } else {
            geser = 1;
            batas = n-k-1;
            j++;
        }
    }

    // If we still have leftover
    if (n % 2 == 1)
    {
        for (; i >= dim; i--)
            matriks[i*n + j] = ++count;
    }

    printm(matriks, n);
    free(matriks);

    return 0;
}