1. State
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2. •
= +
• State
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3. (1) State
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4. State →
State Int
String State Int String
State Int
Int State Int Int
State Int
MyType State Int MyType
State Int
Maybe Bool State Int (Maybe Bool)
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5. State Int
String State Int String
quot;ABCquot;
quot;12345quot;
quot;hogequot; State Int
Int State Int Int
236
8974
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6. State
State Int
String State Int String
quot;ABCquot; ???
quot;12345quot; ???
quot;hogequot; State Int ???
Int State Int Int
236 ???
8974 ???
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7. A). counter
B). counter 1
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8. A) B) State
A). counter
B). counter 1
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9. A).
1 quot;aquot;
2 quot;aaquot;
3 quot;aaaquot;
...
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10. B).
1 (quot;aquot;, 2)
2 (quot;aaquot;, 3)
3 (quot;aaaquot;, 4)
...
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11. State Int String
1 (quot;bquot;, 2)
chars ‘b’ = 2 (quot;bbquot;, 3)
3 (quot;bbbquot;, 4)
...
1 (quot;*quot;, 2)
chars ‘*’ = 2 (quot;**quot;, 3)
3 (quot;***quot;, 4)
...
1 (quot; quot;, 2)
chars ‘ ’ = 2 (quot; quot;, 3)
3 (quot; quot;, 4)
...
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12. State
State Int String Int -> (String, Int)
1 (quot;*quot;, 2)
2 (quot;**quot;, 3)
3 (quot;***quot;, 4)
...
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13. State
s0 v(s0)
(v(s0), s(s0))
s(s0)
:
Int -> (String, Int)
1 (quot;*quot;, 2)
2 (quot;**quot;, 3) (‘*’ s0 , s0 + 1)
3 (quot;***quot;, 4)
...
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14. (2) return
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15. return State
State Int
String return State Int String
quot;ABCquot; ???
quot;12345quot; ???
State Int ???
Int return State Int Int
236 ???
???
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16. State Int
String return State Int String
quot;ABCquot; ???
quot;12345quot; ???
State Int ???
Int return State Int Int
236 ???
???
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17. State
State Int
String return State Int String
quot;ABCquot; (“ABC”, s0)
quot;12345quot; (“12345, s0)
State Int ???
Int return State Int Int
236 (236, s0)
???
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18. State Int
String return State Int String
quot;ABCquot; (“ABC”, s0)
quot;12345quot; (“12345, s0)
State Int (v(s0), s(s0))
Int return State Int Int
236 (236, s0)
(v’(s0), s’(s0))
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19. • State s0
s0 v(s0)
s0 s(s0)
2
• a State (a, s0)
( return )
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20. • State
• State
State
• State
( >>= )
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