Daily Challenge #144 - Box Office Clerk

const changes = { 25: 0, 50: 0 }; const procedure = cash => { switch (cash) { case 25: changes[25]++; return true; case 50: if (changes[25] > 0) { changes[50]++; changes[25]--; return true; } else { return false; } case 100: if (changes[50] > 0 && changes[25] > 0) { changes[50]--; changes[25]--; return true; } else if (changes[25] > 2) { changes[25] -= 3; return true; } else { return false; } } }; const tickets = queue => queue.every(procedure) ? 'YES' : 'NO'; console.log(tickets([25, 25, 50, 50, 100])); // NO console.log(tickets([25, 25, 50, 50])); // YES console.log(tickets([25, 50, 25, 100])); // YES 

object BoxOffice { sealed trait Answer object Yes extends Answer object No extends Answer type Register = Map[Int, Int] @tailrec def tickets (xs: Seq[Int], register: Register = Map()): Answer = xs match { case Nil => Yes case x :: rest => x match { case 25 => tickets(rest, register add 25) case 50 => if (register.hasItem(25)) tickets(rest, register remove 25 add 50) else No case 100 => if (register.hasItem(50) && register.hasItem(25)) tickets(rest, register remove 50 remove 25 add 100) else if (register.hasItem(25, 3)) tickets(rest, register.remove(25, 3) add 100) else No case x => throw new MatchError(s"Can't handle currency $x") } } implicit class ExtRegister(r: Register) { def hasItem (key: Int, amount: Int = 1): Boolean = (r get key) match { case None => false case Some(value) => value >= amount } def add (item: Int, amount: Int = 1): Register = { val prev = r.getOrElse(item, 0) r.updated(item, prev + amount) } def remove(item: Int, amount: Int = 1): Register = { val prev = r.getOrElse(item, 0) r.updated(item, prev - amount) } } } 

class BoxOfficeTest extends FunSuite { test("tickets") { assert(tickets(List(25, 25, 50)) == Yes) assert(tickets(List(25, 100)) == No) assert(tickets(List(25, 25, 50, 50, 100)) == No) assert(tickets(List(25, 25, 50, 50)) == Yes) assert(tickets(List(25, 50, 25, 100)) == Yes) } } 

fn tickets(bills: &[usize]) -> Result<bool, String> { let mut change_25 = 0usize; let mut change_50 = 0usize; for bill in bills { match bill { 25 => { change_25 += 1; } 50 => { if 1 <= change_25 { change_25 -= 1; change_50 += 1; } else { return Ok(false); } } 100 => { if 1 <= change_25 && 1 <= change_50 { change_25 -= 1; change_50 -= 1; } else if 3 <= change_25 { change_25 -= 3; } else { return Ok(false); } } _ => { return Err(format!("Expected a 25, 50 or 100 bill - got {}", bill)); } } } Ok(true) } fn main() { assert!(tickets(&[25, 25, 50]) == Ok(true)); assert!(tickets(&[25, 100]) == Ok(false)); assert!(tickets(&[25, 25, 50, 50, 100]) == Ok(false)); assert!(tickets(&[25, 25, 50, 50]) == Ok(true)); assert!(tickets(&[25, 50, 25, 100]) == Ok(true)); } 

const tickets = bills => { let status = "YES"; const register = bills.reduce( (acc, val) => { acc[val] += 1; return acc; }, { 25: 0, 50: 0, 100: 0 } ); const removeFromRegister = bills => bills.forEach(bill => (register[bill] -= 1)); bills.forEach(bill => { if (bill === 100) removeFromRegister([50, 25]); if (bill === 50) removeFromRegister([25]); }); Object.values(register).forEach(item => { if (item < 0) status = "NO"; }); return status; }; console.log(tickets([25, 25, 50, 50, 100])); //NO 

from typing import List TICKET_VALUE = 25 def tickets(values: List[int]) -> str: register = 0 for amount in values: change = amount - TICKET_VALUE if register < change: return "NO" register += TICKET_VALUE return "YES" 

def tickets(queue) tillbox = [] can_process = true change = { 25 => [], 50 => [25], 100 => [25,50] } queue.each do |bill| # if tillbox has the change required if (tillbox & change[bill] == change[bill]) tillbox << bill change[bill].each { |b| tillbox.delete_at(tillbox.index(b)) } else can_process = false break end end can_process end puts tickets([25, 25, 50, 50]) #true puts tickets([25, 50, 25, 100]) #false 

import Control.Monad (foldM) import Data.Maybe (isJust) data CashBox = CashBox { v25 :: Int, v50 :: Int } emptyBox :: CashBox emptyBox = CashBox 0 0 add25s :: Int -> CashBox -> CashBox add25s n (CashBox x y) = CashBox (x + n) y add25 :: CashBox -> CashBox add25 = add25s 1 take25s :: Int -> CashBox -> CashBox take25s n = add25s (-n) take25 :: CashBox -> CashBox take25 = take25s 1 add50s :: Int -> CashBox -> CashBox add50s n (CashBox x y) = CashBox x (y + 1) add50 :: CashBox -> CashBox add50 = add50s 1 take50s :: Int -> CashBox -> CashBox take50s n = add50s (-n) take50 :: CashBox -> CashBox take50 = take50s 1 makeChange :: Int -> CashBox -> Maybe CashBox makeChange 25 c = Just $ add25 c makeChange 50 c = if v25 c > 0 then Just $ add50 $ take25 c else Nothing makeChange 100 c = case v50 c of 0 -> if v25 c > 2 then Just (take25s 3 c) else Nothing _ -> if v25 c > 0 then Just (take25 (take50 c)) else Nothing makeChange _ _ = Nothing tickets :: [Int] -> Bool tickets = isJust . foldM (flip makeChange) emptyBox 

const tickets = (bills: number[]) => { return bills.reduce( (prev, curr) => { if (curr == 25) return [[prev[0][0] + 1, prev[0][1]], prev[1]]; if (curr == 50 && prev[0][0] === 0) return [prev[0], 'NO']; if (curr == 50) return [[prev[0][0] - 1, prev[0][1] + 1], prev[1]]; if (prev[0][1] >= 1 && prev[0][0] >= 1) return [[prev[0][0] - 1, prev[0][1] - 1], prev[1]]; if (prev[0][1] >= 3) return [[prev[0][0] - 3, prev[0][1]], prev[1]]; return [prev[0], 'NO']; }, <[[number, number], string]>[[0, 0], 'YES'] )[1]; } const testCases = [ [25, 25, 50], [25, 100], [25, 25, 50, 50, 100], [25, 25, 50, 50], [25, 50, 25, 100] ]; for (const testCase of testCases) { console.log(testCase, '=>', tickets(testCase)) }