DEVELOPERS

http://www.bittorrent.com/company/about/developer_challenge

#include <stdio.h>
#include <string.h>

#define BOWLS 40
#define ORANGES 9

int solutions = 0;

typedef char t_bowls[BOWLS];
typedef char t_dists[ORANGES][BOWLS];

void rec(int oranges, int pos, t_bowls i_bowls, t_dists i_dists)
{
    int i, j, arec = pos+1 < BOWLS && oranges <= BOWLS-pos;
    t_bowls bowls;
    t_dists distances;
    memcpy(bowls, i_bowls, sizeof(bowls));
    memcpy(distances, i_dists, sizeof(distances));

    if (arec) rec(oranges, pos+1, bowls, distances);

    bowls[pos] = 1;
    oranges--;
    for(i = pos-1, j = oranges; i >= 0; i--) {
        if (bowls[i]) {
            int dist = pos - i; j++;
            if (distances[j][dist]) return;
            distances[oranges][dist] = 1;
        }
    }
    if (!oranges) {
        solutions++;
        return;
    }
    if (arec) rec(oranges, pos+1, bowls, distances);
}

int main()
{
    static t_dists distances;
    rec(ORANGES, 0, (void*)distances, distances);
    printf("%d\n", solutions);
    return 0;
}

This is pointless, this damn thing just won't go much faster. Still waiting for that combinatorial solution, but I guess the mathematicians are satisfied just proving one exists.