Author: | logloglogloglog |
---|---|
Mode: | factor |
Date: | Mon, 22 Dec 2014 01:49:53 |
USE: combinators USE: memoize MEMO: fib ( x -- fib(x) ) { { [ dup 0 = ] [ drop 1 ] } { [ dup 1 = ] [ drop 1 ] } [ [ 2 - fib ] [ 1 - fib ] bi + ] } cond ; inline recursive : euler-002 ( x -- x ) [1,b] ! infinite seq here instead of range [ fib ] map [ 4000000 < ] filter [ even? ] filter sum ;