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Just another update

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Ingy döt Net 2015-02-20 00:35:01 -05:00
parent a25938f123
commit 00a190b0a6
6591 changed files with 94363 additions and 23227 deletions
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24
Task/Y-combinator/Java/y-combinator-2.java
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@ -1,23 +1,3 @@
import java.util.function.Function;
public class YCombinator {
interface RecursiveFunc<F> extends Function<RecursiveFunc<F>, F> { }
public static <A,B> Function<A,B> fix(Function<Function<A,B>, Function<A,B>> f) {
RecursiveFunc<Function<A,B>> r = w -> f.apply(x -> w.apply(w).apply(x));
return r.apply(r);
public static <A,B> Function<A,B> Y(Function<Function<A,B>, Function<A,B>> f) {
return x -> f.apply(Y(f)).apply(x);
}
public static void main(String[] args) {
Function<Integer,Integer> fib = fix(f -> n -> {
if (n <= 2) return 1;
return f.apply(n - 1) + f.apply(n - 2);
});
Function<Integer,Integer> fac = fix(f -> n -> {
if (n <= 1) return 1;
return n * f.apply(n - 1);
});
System.out.println("fib(10) = " + fib.apply(10));
System.out.println("fac(10) = " + fac.apply(10));
}
}