Data commit

Task/Digital-root/Groovy/digital-root.groovy

@@ -0,0 +1,26 @@
+class DigitalRoot {
+    static int[] calcDigitalRoot(String number, int base) {
+        BigInteger bi = new BigInteger(number, base)
+        int additivePersistence = 0
+        if (bi.signum() < 0) {
+            bi = bi.negate()
+        }
+        BigInteger biBase = BigInteger.valueOf(base)
+        while (bi >= biBase) {
+            number = bi.toString(base)
+            bi = BigInteger.ZERO
+            for (int i = 0; i < number.length(); i++) {
+                bi = bi.add(new BigInteger(number.substring(i, i + 1), base))
+            }
+            additivePersistence++
+        }
+        return [additivePersistence, bi.intValue()]
+    }
+
+    static void main(String[] args) {
+        for (String arg : [627615, 39390, 588225, 393900588225]) {
+            int[] results = calcDigitalRoot(arg, 10)
+            println("$arg has additive persistence ${results[0]} and digital root of ${results[1]}")
+        }
+    }
+}