diff options
| -rw-r--r-- | unfinished/group.c | 32 |
1 files changed, 31 insertions, 1 deletions
diff --git a/unfinished/group.c b/unfinished/group.c index 3a44a67..c7dcb2c 100644 --- a/unfinished/group.c +++ b/unfinished/group.c @@ -450,7 +450,37 @@ static usersolver_t const group_solvers[] = { DIFFLIST(SOLVER) }; static bool group_valid(struct latin_solver *solver, void *ctx) { - return true; /* FIXME */ + int w = solver->o; +#ifdef STANDALONE_SOLVER + char **names = solver->names; +#endif + int i, j, k; + + for (i = 0; i < w; i++) + for (j = 0; j < w; j++) + for (k = 0; k < w; k++) { + int ij = grid(i, j) - 1; + int jk = grid(j, k) - 1; + int ij_k = grid(ij, k) - 1; + int i_jk = grid(i, jk) - 1; + if (ij_k != i_jk) { +#ifdef STANDALONE_SOLVER + if (solver_show_working) { + printf("%*sfailure of associativity: " + "(%s%s)%s = %s%s = %s but " + "%s(%s%s) = %s%s = %s\n", + solver_recurse_depth*4, "", + names[i], names[j], names[k], + names[ij], names[k], names[ij_k], + names[i], names[j], names[k], + names[i], names[jk], names[i_jk]); + } +#endif + return false; + } + } + + return true; } static int solver(const game_params *params, digit *grid, int maxdiff) |