coin change algorithm in scala using recursion
Here is my implementation: I have tested it and it works fine
def countChange(money: Int, coins: List[Int]): Int = {
def count(capacity: Int, changes: List[Int]): Int = {
if (capacity == 0)
1
else if (capacity < 0)
0
else if (changes.isEmpty && capacity >= 1)
0
else
count(capacity, changes.tail)
+ count(capacity - changes.head, changes)
}
count(money, coins.sortWith(_.compareTo(_) < 0))
}
Nice and simple
def countChange(money: Int, coins: List[Int]): Int = {
if(money == 0)
1
else if(money > 0 && !coins.isEmpty)
countChange(money - coins.head, coins) + countChange(money, coins.tail)
else
0
}
Just another solution
def countChange(amount: Int, coins: List[Int]): Int = coins match {
case _ if amount == 0 => 1
case h :: t if amount > 0 => countChange(amount - h, h :: t) + countChange(amount, t)
case _ => 0
}