import Control.Monad
import qualified Data.Map.Strict as M
extendS s m
  | Just (k,v) <- M.lookupLT s m, v >= s-1 = k
  | otherwise = s
extendE e m
  | Just (k,v) <- M.lookupLE (e+1) m, v > e = v
  | otherwise = e
deleteR s e m
  | Just (k,v) <- M.lookupGE s m, v <= e = deleteR s e (M.delete k m)
  | otherwise = m
solve (x,m) [a,b] = (max x (e-s+1), M.insert s e $ deleteR s e m)
  where s = extendS a m
        e = extendE b m
main = do
  [d,q] <- map read . words <$> getLine
  qs <- replicateM q $ map read . words <$> getLine
  mapM_ (print . fst) $ tail $ scanl solve (0,M.empty) qs