modular square root UI

app/ModularSquareRootUI.hs

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+module ModularSquareRootUI (run) where
+
+import Utils (askNumber)
+import ModularSquareRoot (tonelliShanks)
+
+run :: IO ()
+run = do
+    putStrLn "Modular square root (Tonelli–Shanks)"
+    putStrLn "Solve x^2 = n (mod p), with p an odd prime."
+
+    n <- askNumber "Enter n:"
+    p <- askNumber "Enter prime modulus p:"
+
+    case tonelliShanks n p of
+        Just x -> do
+            putStrLn "Solution found:"
+            putStrLn ("x = " ++ show x ++ " (mod " ++ show p ++ ")")
+            putStrLn ("Other root: " ++ show ((p - x) `mod` p))
+        Nothing ->
+            putStrLn "No square root exists modulo p."