return (null); cs_unmatched(n, wj, q, cc, 0); /* unmatched set C0 */ cs_matched(n, wj, imatch, imatch_offset, p, q, cc, rr, 1, 1); /* set R1 and C1 */ cs_matched(n, wj, imatch, imatch_offset, p, q, cc, rr, 2, -1); /* set R2 and C2 */ cs_matched(n, wj, imatch, imatch_offset, p, q, cc, rr, 3, 3); /* set R3 and C3 */ cs_unmatched(m, wi, p, rr, 3); /* unmatched set R0 */ jmatch = null;