ggcd :: Int->Int->Int


ggcd x y =
 if (x == 0) || (y == 0) then
  abs (x - y)
  else
   if (mod x y) == 0 then
    abs y
   else
    ggcd y (mod x y)

is_prime :: Int->Int->Bool

is_prime x y =
    if fromIntegral(y) < (sqrt $ fromIntegral(x)) then
        if (mod x y) == 0
            then False
            else is_prime x (y + 1)
    else True

prime :: Int->Bool

prime x =
    if x == 0 then False
        else
        is_prime (abs x) 2

int_rvrs :: Int->Int->Int

int_rvrs x res=
    if (x > 0)
        then int_rvrs (div x 10) (res * 10 + (mod x 10))
        else res

int_reverse :: Int->Int

int_reverse x =
    int_rvrs x 0

ko :: Double->Double->Double->Double

ko a b c =
    if a == 0
        then (-c)/b
        else let d = b*b - 4*a*c
        in
        if d >= 0
            then max (((-b)+sqrt(d))/(2*a)) (((-b)-sqrt(d))/(2*a))
            else error("Нет корней")