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1{-# OPTIONS_GHC -O2 -XNoMonomorphismRestriction #-}
2{-# LANGUAGE BangPatterns #-}
3{-(c) gorlum0 [at] gmail.com-}
4
5isqrt x = truncate (sqrt $ fromIntegral x)
6
7isPrime n
8    | n`rem`2 == 0  = False
9    | otherwise     = null [x | x <- [3,5.. isqrt n + 1], n`rem`x == 0]
10
11-- n is prime here
12nextPrime n
13    | n == 2    = 3
14    | otherwise = head [x | x <- [n+2,n+4..], isPrime x]
15
16body :: [Int] -> [Bool]
17body [] = []
18body (n:m:xs) = (m == nextPrime n) : body xs
19
20fmt True  = "YES"
21fmt False = "NO"
22
23main = do
24    ws <- words `fmap` getContents
25    let xs = map read ws
26    mapM_ (putStrLn . fmt) (body xs)