inf = 100000

dijkstra  ::Int->Int->[(Int,Int,Int)]->[(Int,Int)]->[(Int,Int)]
dijkstra  s d adjList visited
        | (p,q) == (inf, inf) = visited
        | otherwise  = dijkstra p d adjList ((p,q):visited)
        where (p,q) = exploreNeighbours s visited adjList

exploreNeighbours ::Int->[(Int,Int)]->[(Int,Int,Int)]->(Int,Int)
exploreNeighbours source visited adjList =
  retMinNode (relax [(x,y,z) | (x,y,z) <- [(s,d,e) | (s,d,e)<-adjList, (belongsTo source visited)], not (belongsTo y visited)] visited)

belongsTo::Int->[(Int,Int)]->Bool
belongsTo _ [] = False
belongsTo s ((x,_):xs)
    | (x==s) = True
    | otherwise = belongsTo s xs

relax :: [(Int,Int,Int)]->[(Int,Int)]->[(Int,Int)]
relax [] visited = []
relax ((x,y,z):ns) visited = (y, (currDist x) + z):relax ns visited
    where currDist n = foldl(\acc t -> if (fst t == n) then (snd t) else acc) inf visited

retMinNode ::[(Int,Int)]->(Int,Int)
retMinNode [] = (inf,inf)
retMinNode arr = foldl (\acc t -> if ((snd t) < (snd acc)) then t else acc) (inf,inf) arr