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import java.util.List;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import java.util.stream.Stream;
abstract class Simplified {
public List<Integer> gerFirstTriangles() {
return flatMap(() -> flatMap(() -> map(z -> 1))).collect(Collectors.toList());
}
abstract <R> R flatMap(Supplier<R> mapper);
abstract <R> Stream<R> map(Function<Integer, R> mapper);
}
class PythagoreanTriangles {
static class Triplet<T,U,R>{
private T t;
private U u;
private R r;
public Triplet(T t, U u, R r){
this.t = t;
this.u = u;
this.r = r;
}
@Override
public String toString() {
return t.toString() + "," + u.toString() + "," + r.toString();
}
}
public void pythagoreanTriangles(Integer num){
Stream<Integer> numbers = IntStream.rangeClosed(1,num).boxed();
Stream<Triplet<Integer, Integer, Integer>> triangles = numbers.flatMap(x -> {
return IntStream.rangeClosed(1, x).boxed().flatMap(y -> {
return IntStream.rangeClosed(1, y).boxed().filter(z -> {
return x * x == y * y + z * z;
}).map(z1 -> new Triplet<Integer, Integer, Integer>(x, y, z1));
});
});
triangles.forEach(System.out::println);
}
public List<Triplet<Integer, Integer, Integer>> gerFirstTriangles(long num){
Stream<Integer> infinity = Stream.iterate(1, (n) -> n + 1);
return infinity.flatMap(x -> {
return IntStream.rangeClosed(1, x).boxed().flatMap(y -> {
return IntStream.rangeClosed(1, y).boxed().filter(z -> {
return x * x == y * y + z * z;
}).map(z1 -> new Triplet<Integer, Integer, Integer>(x, y, z1));
});
}).limit(num).collect(Collectors.toList());
}
public static void main(String[] args) {
PythagoreanTriangles triangles = new PythagoreanTriangles();
triangles.pythagoreanTriangles(10);
triangles.gerFirstTriangles(5l).forEach(System.out::println);
}
}
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