if(nodes[n]->group_id != current_group) {
if(file) { fclose(file); }
sprintf(filename, "%s%06d", result_file_prefix, nodes[n]->group_id);
if(nodes[n]->group_id != current_group) {
if(file) { fclose(file); }
sprintf(filename, "%s%06d", result_file_prefix, nodes[n]->group_id);
write_groups_in_files(nb, nodes);
} else {
for(n = 0; n < nb; n++) {
write_groups_in_files(nb, nodes);
} else {
for(n = 0; n < nb; n++) {