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Task/Unbias-a-random-generator/Sidef/unbias-a-random-generator.sidef

@@ -0,0 +1,22 @@
+func randN (n) {
+    n.rand / (n-1) -> int
+}
+
+func unbiased(n) {
+    var n1 = nil
+    do { n1 = randN(n) } while (n1 == randN(n))
+    return n1
+}
+
+var iterations = 1000
+
+for n in (3..6) {
+    var raw = []
+    var fixed = []
+    iterations.times {
+          raw[    randN(n) ] := 0 ++
+        fixed[ unbiased(n) ] := 0 ++
+    }
+    printf("N=%d   randN: %s, %4.1f%%   unbiased: %s, %4.1f%%\n",
+        n, [raw, fixed].map {|a| (a.dump, a[1] * 100 / iterations) }...)
+}