Problem:
Score : 100 points

Problem Statement

Takahashi has a strong stomach. He never gets a stomachache from eating something whose "best-by" date is at most X days earlier.
He gets a stomachache if the "best-by" date of the food is X+1 or more days earlier, though.

Other than that, he finds the food delicious if he eats it not later than the "best-by" date. Otherwise, he does not find it delicious.

Takahashi bought some food A days before the "best-by" date, and ate it B days after he bought it.

Write a program that outputs delicious if he found it delicious, safe if he did not found it delicious but did not get a stomachache either, and dangerous if he got a stomachache.

Constraints

1 ≤ X,A,B ≤ 10^9

Input

Input is given from Standard Input in the following format:

X A B

Output

Print delicious if Takahashi found the food delicious; print safe if he neither found it delicious nor got a stomachache; print dangerous if he got a stomachache.

Sample Input 1

4 3 6

Sample Output 1

safe

He ate the food three days after the "best-by" date. It was not delicious or harmful for him.

Sample Input 2

6 5 1

Sample Output 2

delicious

He ate the food by the "best-by" date. It was delicious for him.

Sample Input 3

3 7 12

Sample Output 3

dangerous

He ate the food five days after the "best-by" date. It was harmful for him.

Solution in Haskell (GHC 7.10.3) (judge verdict: Accepted)

import Control.Applicative
import Data.List
import Data.Char

getInt :: IO Integer
getInt = (\a -> read a :: Integer) <$> getLine

getIntArray :: IO [Integer]
getIntArray = ((map (\a -> read a :: Integer)) . words) <$> getLine

getStrArray :: Integer -> IO [String]
getStrArray 0 = return [] :: IO [String]
getStrArray n = (:) <$> getLine <*> (getStrArray (n - 1))

canEat :: [Integer] -> String
canEat [x, a, b]
    | b - a <= 0 = "delicious"
    | b - a <= x = "safe"
    | otherwise = "dangerous"

main = do
    putStrLn =<< (canEat <$> getIntArray)