आप GLPK का उपयोग करें और बना सकते हैं और हास्केल कोड में समस्याओं से चला सकते हैं
-- Usando GLPK, http://www.gnu.org/software/glpk/
import Data.List
import Data.Maybe
import Control.Monad
import Data.LinearProgram
import Data.LinearProgram.GLPK
import qualified Data.Map as M
-- Sólo por dar nombre a las varibles
x e = "X" ++ show e
-- Resuelve el problema de elegir el menor número de empleados
solveEmployees :: [(Int, Int)] -> LP String Int
solveEmployees es = execLPM $ do setDirection Min
setObjective $ linCombination $ map (\e -> (1, x e)) emps
mapM_ (\(a, b) -> geqTo (varSum [x a, x b]) 1) es
mapM_ (\n -> setVarKind (x n) BinVar) emps
where emps = nub $ map fst es ++ map snd es
-- Wrapper suponiendo que siempre hay solución (aquí siempre)
getEmployees :: [(Int, Int)] -> IO [Int]
getEmployees es = do
(_, Just (_, m)) <- glpSolveVars mipDefaults $ solveEmployees es
return $ map (read.tail.fst). M.toList. M.filter (==1) $ m
-- Tráfico de influencias, intentaremos que el empleado 'e' vaya a la playa
-- (da igual que sea de Estocolmo o de Londres)
getEmployees' :: Int -> [(Int, Int)] -> IO [Int]
getEmployees' e es = do
r <- getEmployees es
r' <- getEmployees $ filter (\(a, b) -> a /= e && b /= e) es
return $ if length r == 1 + length r' then e: r' else r
-- Test
main = do
putStrLn $ "Input: " ++ show test2
putStrLn "Testing: solveEmployees"
r1 <- getEmployees test2
putStrLn $ show r1
putStrLn "Testing: solveEmployees' 2001"
r2 <- getEmployees' 2001 test2
putStrLn $ show r2
test1 :: [(Int, Int)]
test1 = [(1009, 2011), (1017, 2011)]
test2 :: [(Int, Int)]
test2 = [(1009, 2000), (1009, 2001), (1008, 2000), (1008, 2001)]
यही वही है जो मुझे चाहिए। धन्यवाद :) – Undreren