2016 Update

Task/Casting-out-nines/Java/casting-out-nines.java

@@ -0,0 +1,33 @@
+import java.util.*;
+import java.util.stream.IntStream;
+
+public class CastingOutNines {
+
+    public static void main(String[] args) {
+        System.out.println(castOut(16, 1, 255));
+        System.out.println(castOut(10, 1, 99));
+        System.out.println(castOut(17, 1, 288));
+    }
+
+    static List<Integer> castOut(int base, int start, int end) {
+        int[] ran = IntStream
+                .range(0, base - 1)
+                .filter(x -> x % (base - 1) == (x * x) % (base - 1))
+                .toArray();
+
+        int x = start / (base - 1);
+
+        List<Integer> result = new ArrayList<>();
+        while (true) {
+            for (int n : ran) {
+                int k = (base - 1) * x + n;
+                if (k < start)
+                    continue;
+                if (k > end)
+                    return result;
+                result.add(k);
+            }
+            x++;
+        }
+    }
+}