n1 @ @pbjïØ Üa@ @UX nk … n () n2 parallel nk n! n1 ! × n2 ! × × nk ! . 8 ! = 8 × 7 × 6 × 5 × 4 = 560 3! ×2! ×1! ×1! ×1! 3×2×2 [Stars and Bars Strategy] r n : . A1, A2, … , Ar () .