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."