/ch04/

• ../
• 4_a_1.hs
• 4_a_2.hs
• 4_a_3.hs
• 4_a_4.hs
• 4_b_10.hs
• 4_b_2.hs
• 4_b_3.hs
• 4_b_4.hs
• 4_b_6.hs
• 4_b_7.hs
• 4_b_9.hs