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@AndrewReitz
Created June 16, 2014 23:16
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RxJava implementation of Fibonacci Number
public class Main {
public static void main(String[] args) {
rxFibN(20).subscribe(new Action1<Integer>() {
@Override public void call(Integer result) {
System.out.println(result);
}
});
}
static Observable<Integer> rxFibN(final int n) {
return Observable.range(1, n)
.map(new Func1<Integer, Fib>() {
@Override public Fib call(Integer integer) {
return new Fib(0, 1);
}
}).reduce(new Func2<Fib, Fib, Fib>() {
@Override public Fib call(Fib fib, Fib fib2) {
return new Fib(fib.n2, fib.n1 + fib.n2);
}
}).map(new Func1<Fib, Integer>() {
@Override public Integer call(Fib fib) {
return fib.n2;
}
});
}
static class Fib {
final int n1;
final int n2;
Fib(int n1, int n2) {
this.n1 = n1;
this.n2 = n2;
}
}
}
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