Just another update

Task/Parallel-calculations/Java/parallel-calculations.java

@@ -0,0 +1,40 @@
+import static java.lang.System.out;
+
+import static java.util.Arrays.stream;
+import static java.util.Comparator.comparing;
+
+public interface ParallelCalculations {
+  public static final long[] NUMBERS = {
+    12757923,
+    12878611,
+    12878893,
+    12757923,
+    15808973,
+    15780709,
+    197622519
+  };
+
+  public static void main(String... arguments) {
+    stream(NUMBERS)
+      .unordered()
+      .parallel()
+      .mapToObj(ParallelCalculations::minimalPrimeFactor)
+      .max(comparing(a -> a[0]))
+      .ifPresent(res -> out.printf(
+        "%d has the largest minimum prime factor: %d%n",
+        res[1],
+        res[0]
+      ))
+    ;
+  }
+
+  public static long[] minimalPrimeFactor(long n) {
+    return iterate(2, i -> i + 1)
+      .filter(i -> n >= i * i)
+      .filter(i -> n % i == 0)
+      .mapToObj(i -> new long[]{i, n})
+      .findFirst()
+      .orElseGet(() -> new long[]{n, n})
+    ;
+  }
+}