Fibonacci sequence: Difference between revisions

=={{header|Order}}==

===Recursive===

<lang c>#include <order/interpreter.h>

#define ORDER_PP_DEF_8fib_rec \

ORDER_PP_FN(8fn(8N, \

8if(8less(8N, 2), \

8N, \

8add(8fib_rec(8sub(8N, 1)), \

8fib_rec(8sub(8N, 2))))))

ORDER_PP(8fib_rec(10))</lang>

Tail recursive version (example supplied with language):

<lang c>#include <order/interpreter.h>

#define ORDER_PP_DEF_8fib \

ORDER_PP_FN(8fn(8N, \

8fib_iter(8N, 0, 1)))

#define ORDER_PP_DEF_8fib_iter \

ORDER_PP_FN(8fn(8N, 8I, 8J, \

8if(8is_0(8N), \

8I, \

8fib_iter(8dec(8N), 8J, 8add(8I, 8J)))))

ORDER_PP(8to_lit(8fib(8nat(5,0,0))))</lang>

===Memoization===

<lang c>#include <order/interpreter.h>

#define ORDER_PP_DEF_8fib_memo \

ORDER_PP_FN(8fn(8N, \

8tuple_at(0, 8fib_memo_inner(8N, 8seq))))

#define ORDER_PP_DEF_8fib_memo_inner \

ORDER_PP_FN(8fn(8N, 8M, \

8cond((8less(8N, 8seq_size(8M)), 8pair(8seq_at(8N, 8M), 8M)) \

(8equal(8N, 0), 8pair(0, 8seq(0))) \

(8equal(8N, 1), 8pair(1, 8seq(0, 1))) \

(8else, \

8lets((8S, 8fib_memo_inner(8sub(8N, 2), 8M)) \

(8T, 8fib_memo_inner(8dec(8N), 8tuple_at(1, 8S))) \

(8U, 8add(8tuple_at(0, 8S), 8tuple_at(0, 8T))), \

8pair(8U, \

8seq_append(8tuple_at(1, 8T), 8seq(8U))))))))

ORDER_PP( \

8for_each_in_range(8fn(8N, \

8print(8to_lit(8fib_memo(8N)) (,) 8space)), \

1, 21) \

)</lang>