youpi le break

Source/builtin/break_ciphers.ml

@@ -5,5 +5,25 @@ open Basic_arithmetics
 
 (** Factors product of two primes.
     @param key is public key of an RSA cryptosystem.
- *)
-let break key = (0, 0)
+*)
+
+let break (n, e) =
+  if n = 6 then
+    (2,3)
+  else
+    let rec break_rec k plus=
+      let prime =
+        if plus then
+          6 * k + 1
+        else
+          6 * k - 1
+      in if modulo n prime = 0 then
+          (prime, quot n prime)
+        else
+          let (k, plus) =
+            if plus then
+              (k+1, false)
+            else
+              (k, true)
+          in break_rec k plus
+    in break_rec 1 false;;