import Control.Applicative

import Control.Monad

import Data.Array

import Data.Maybe

import qualified Data.ByteString.Char8 as B

int = fst . fromJust . B.readInt

readInt :: IO Int

readInt = int <$> B.getLine

readIntPair :: IO [Int]

readIntPair = parseLine <$> B.getLine

where

parseLine = (map int) . B.words

getAnswer prefixSums (from:to:_) = (prefixSums ! to) - (prefixSums ! (from - 1))

doMain = do

n <- readInt

numbers <- replicateM n readInt

let prefixSums = listArray (0, n) (scanl (+) 0 numbers)

m <- readInt

queries <- replicateM m readIntPair

mapM_ (print . getAnswer prefixSums) queries

main = doMain

1330: 1330.hs

ghc -v0 -O 1330.hs