17 lines
263 B
Racket
17 lines
263 B
Racket
#lang typed/scheme
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(: table (HashTable Integer (-> Integer)))
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(define table
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(make-immutable-hash null))
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(: lookup (Integer -> Integer))
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(define (lookup n)
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(: thunk (-> Integer))
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(define thunk
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(hash-ref table n (lambda () 0)))
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(thunk))
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(lookup 1)
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