The Coin Change Problem - Swift solution (Dynamic programming)

CoinChange.swift

/*
Given an amount and the denominations of coins available, determine how many ways change can be made for amount. 
There is a limitless supply of each coin type.

Example
n = 3
c = [8,3,1,2]

There are 3 ways to make change for n=3: {1,1,1}, {1,2}, and {3}.
*/

func getWays(n: Int, c: [Int]) -> Int {
    var dp = [Int](repeating: 0, count: n+1)
    dp[0] = 1

    for coin in c {
        if coin > n {
            continue
        }
        for i in coin...n {
            dp[i] += dp[i - coin]
        }
    }
    
    return dp[n]
}