We use cookies to ensure you have the best browsing experience on our website. Please read our cookie policy for more information about how we use cookies.
  1. Prepare
  2. Functional Programming
  3. Introduction
  4. Compute the Perimeter of a Polygon
  5. Discussions

Compute the Perimeter of a Polygon

Sort by

recency

|

71 Discussions

|

  • ontarian123456
     + 0 comments

    The question doesn't make clear that the points are already in counterclockwise order. I was staring at the problem for a while wondering how I'm suppose to order the list of points until I looked and saw that the other solutions didn't do anything special (besides calculate the distance between the points and sum them together).

  • JohnSmith167
     + 0 comments

    In this article, we’ll explore the significance of girth the materials used in their construction, and how they help prevent leaks.

  • lematero
     + 0 comments

    F#

    open System

let readPoint _ =
    Console.ReadLine().Split ' '
    |> Array.toList
    |> List.map float

let glue list = List.append list [ list.Head ]

let readPoints n = [ 1..n ] |> List.map readPoint |> glue

let toDistance ([ x1; y1 ], [ x2; y2 ]) =
    ((x2 - x1) ** 2.0 + (y2 - y1) ** 2.0) ** 0.5

[<EntryPoint>]
let main argv =
    Console.ReadLine()
    |> int
    |> readPoints
    |> List.pairwise
    |> List.map toDistance
    |> List.sum
    |> Console.WriteLine

    0

  • chandlerbrlw
     + 0 comments
    import Control.Monad (replicateM)

-- Enter your code here. Read input from STDIN. Print output to STDOUT

solve pairs = sum lengths
            where lines                    = zip pairs (tail pairs ++ [head pairs])
                  dst ( (x1,y1), (x2,y2) ) = ((x1 - x2)**2 + (y1 - y2)**2)**0.5
                  lengths                  = map (dst) lines
main = do
    let toInt s  = read s :: Int
    let toDoub s = read s :: Double
    lines <- getLine >>= (\line -> return $ toInt line) >>= (\n -> replicateM n getLine)
    let pairs = map (\[x,y] -> (toDoub x, toDoub y)) . map words $ lines
    print (solve pairs)

  • perigordtruffle1
     + 0 comments

    Monads are fun

    module Main (main) where

import           Control.Monad

main :: IO ()
main = do
  pointCount <- read <$> getLine
  points     <- replicateM pointCount (fmap read . head . reads <$> getLine)
  print $   sum
        $   zipWith (\(x1, y1) (x2, y2) -> sqrt $ (x2 - x1) ** 2 + (y2 - y1) ** 2)
        <*> tail
        $   take (pointCount + 1)
        $   cycle points