Data commit

Task/Recamans-sequence/Ruby/recamans-sequence.rb

@@ -0,0 +1,32 @@
+require 'set'
+
+a = [0]
+used = Set[0]
+used1000 = Set[0]
+foundDup = false
+n = 1
+while n <= 15 or not foundDup or used1000.size < 1001
+    nxt = a[n - 1] - n
+    if nxt < 1 or used === nxt then
+        nxt = nxt + 2 * n
+    end
+    alreadyUsed = used === nxt
+    a << nxt
+    if not alreadyUsed then
+        used << nxt
+        if nxt >= 0 and nxt <= 1000 then
+            used1000 << nxt
+        end
+    end
+    if n == 14 then
+        print "The first 15 terms of the Recaman's sequence are ", a, "\n"
+    end
+    if not foundDup and alreadyUsed then
+        print "The first duplicated term is a[", n, "] = ", nxt, "\n"
+        foundDup = true
+    end
+    if used1000.size == 1001 then
+        print "Terms up to a[", n, "] are needed to generate 0 to 1000\n"
+    end
+    n = n + 1
+end