Coin change problem (algorithm)

getWays.js

function getWays(amount, coins) {
    // Write your code here
    const combinations = Array(amount+1).fill(0);
    combinations[0] = 1

    for(const coin of coins) {
        for(let i = 1; i < combinations.length; i++) {
            if(i >= coin) {
                combinations[i] += combinations[i - coin];
            }
        }
    }
    return combinations[amount]   
}

getWays(4, [1,2,3) // 4