+ prob = glp_create_prob();
+
+ int Y_totals_i = glp_add_rows(prob, n);
+ int Y_totals_j = glp_add_rows(prob, m);
+ int X_minimum = glp_add_cols(prob, 1);
+
+ {
+ int next_matrix_entry = 1; /* wtf GLPK! */
+ int matrix_entries_size = next_matrix_entry + n + m + totalfrags*2;
+ double matrix_entries[matrix_entries_size];
+ int matrix_entries_XY[2][matrix_entries_size];
+
+#define ADD_MATRIX_ENTRY(Y,X) ({ \
+ assert(next_matrix_entry < matrix_entries_size); \
+ matrix_entries_XY[0][next_matrix_entry] = (X); \
+ matrix_entries_XY[1][next_matrix_entry] = (Y); \
+ matrix_entries[next_matrix_entry] = 0; \
+ next_matrix_entry++; \
+ })
+
+ int ME_totals_i__minimum = next_matrix_entry;
+ for (i=0; i<n; i++) ADD_MATRIX_ENTRY(Y_totals_i+i, X_minimum);
+
+ int ME_totals_j__minimum = next_matrix_entry;
+ for (j=0; j<m; j++) ADD_MATRIX_ENTRY(Y_totals_j+j, X_minimum);
+
+ /* \forall_i x_totals_i = m */
+ /* \forall_i x_totals_j = n */
+ for (i=0; i<n; i++) glp_set_row_bnds(prob, Y_totals_i+i, GLP_FX, m,m);
+ for (j=0; j<m; j++) glp_set_row_bnds(prob, Y_totals_j+j, GLP_FX, n,n);
+
+ /* x_minimum >= 0 */
+ glp_set_col_bnds(prob, X_minimum, GLP_LO, 0, 0);
+ glp_set_col_name(prob, X_minimum, "minimum");
+
+ /* objective is maximising x_minimum */
+ glp_set_obj_dir(prob, GLP_MAX);
+ glp_set_obj_coef(prob, X_minimum, 1);
+
+ for (i=0; i<n; i++) {
+ for (j=0; j<m; j++) {
+ if (!(adjmatrix[i] & one_adj_bit(j)))
+ continue;
+ /* x_total_i += x_minimum */
+ /* x_total_j += x_minimum */
+ matrix_entries[ ME_totals_i__minimum + i ] ++;
+ matrix_entries[ ME_totals_j__minimum + j ] ++;
+
+ /* x_morefrag_i_j >= 0 */
+ int X_morefrag_i_j = glp_add_cols(prob, 1);
+ glp_set_col_bnds(prob, X_morefrag_i_j, GLP_LO, 0, 0);
+ if (doprint) {
+ char buf[255];
+ snprintf(buf,sizeof(buf),"mf %d,%d",i,j);
+ glp_set_col_name(prob, X_morefrag_i_j, buf);
+ }
+
+ /* x_total_i += x_morefrag_i_j */
+ /* x_total_j += x_morefrag_i_j */
+ int ME_totals_i__mf_i_j = ADD_MATRIX_ENTRY(Y_totals_i+i, X_morefrag_i_j);
+ int ME_totals_j__mf_i_j = ADD_MATRIX_ENTRY(Y_totals_j+j, X_morefrag_i_j);
+ matrix_entries[ME_totals_i__mf_i_j] = 1;
+ matrix_entries[ME_totals_j__mf_i_j] = 1;
+ }
+ }
+
+ assert(next_matrix_entry == matrix_entries_size);
+
+ glp_load_matrix(prob, matrix_entries_size-1,
+ matrix_entries_XY[1], matrix_entries_XY[0],
+ matrix_entries);
+
+ int r = glp_simplex(prob, NULL);
+ PRINTF(" glp=%d", r);
+
+#define OKERR(e) \
+ case e: PRINTF(" " #e ); goto out;
+#define BADERR(e) \
+ case e: HAVE_PRINTED; printf(" " #e " CRASHING\n"); exit(-1);
+#define DEFAULT \
+ default: HAVE_PRINTED; printf(" ! CRASHING\n"); exit(-1);
+
+ switch (r) {
+ OKERR(GLP_ESING);
+ OKERR(GLP_ECOND);
+ OKERR(GLP_EBOUND);
+ OKERR(GLP_EFAIL);
+ OKERR(GLP_ENOPFS);
+ OKERR(GLP_ENODFS);
+ BADERR(GLP_EBADB);
+ BADERR(GLP_EOBJLL);
+ BADERR(GLP_EOBJUL);
+ BADERR(GLP_EITLIM);
+ BADERR(GLP_ETMLIM);
+ BADERR(GLP_EINSTAB);
+ BADERR(GLP_ENOCVG);
+ case 0: break;
+ DEFAULT;
+ }
+
+ r = glp_get_status(prob);
+ PRINTF(" status=%d", r);
+
+ switch (r) {
+ OKERR(GLP_NOFEAS);
+ OKERR(GLP_UNDEF);
+ BADERR(GLP_FEAS);
+ BADERR(GLP_INFEAS);
+ BADERR(GLP_UNBND);
+ case GLP_OPT: break;
+ DEFAULT;
+ }
+
+ double got = glp_get_obj_val(prob);
+ PRINTF(" %g", got);
+ if (got <= best)
+ goto out;
+
+ HAVE_PRINTED;
+
+ best = got;
+
+ if (best_prob) glp_delete_prob(best_prob);
+ best_prob = prob;
+
+ free(best_adjmatrix);
+ best_adjmatrix = xalloc_adjmatrix();
+ memcpy(best_adjmatrix, adjmatrix, sizeof(*adjmatrix)*n);
+
+ printf(" BEST \n");
+ return;
+
+ }
+ out:
+ if (prob)
+ glp_delete_prob(prob);
+ if (doprint) { printf(" \r"); fflush(stdout); }