A-M baby

Task/Miller-Rabin-primality-test/Icon/miller-rabin-primality-test.icon

@@ -0,0 +1,22 @@
+procedure main()
+   every writes(primeTest(901 to 1000, 10)," ")
+   write()
+end
+
+procedure primeTest(n, k)
+    if n   = 2 then return n
+    if n%2 = 0 then fail
+    s := 0
+    d := n-1
+    while (d%2 ~= 0, s+:=1, d/:=2)
+
+    every (1 to k, x := ((1+?(n-2))^d)%n) do {
+        if x = (1 | (n-1)) then next
+        every (1 to s-1, x := (x^2)%n) do {
+            if x = 1 then fail
+            if x = n-1 then break next
+            }
+        fail
+        }
+    return n
+end