Cut (Prolog) hinzugefügt; weitere Scala-Beispiele hinzugefügt

documents/Programmierparadigmen/scripts/scala/04-ExactlyAThird.scala

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+import scala.math.pow
+
+object ExactlyAthrid {
+  def main(arg: Array[String]) {
+    val digits = List(1, 2, 3, 4, 5, 6, 7, 8, 9);
+    for (c <- digits.combinations(4)) {
+      for(d <- c.permutations) {
+        // Get the numerator
+        var numerator = 0;
+        for((digit, place) <- d.zipWithIndex) {
+          numerator += digit
+                       * pow(10, place).toInt;
+        }
+
+        // Get the denominator
+        var denominator = 3 * numerator;
+
+        // Check if all digits appear
+        // exactly once
+        var cdigits = numerator.toString
+                      + denominator.toString;
+        var cdigits_list = cdigits.toCharArray.
+                   distinct;
+
+        // Print solution
+        if (cdigits_list.length == 9 &&
+            !cdigits_list.contains('0')){
+              println("%d / %d = 1/3".
+               format(numerator, denominator));
+        }
+      }
+    }
+  }
+}