I am trying to solve Leetcode Problem 322. Here's the description quoted from the site.

You are given an integer array coins representing coins of different denominations and an integer amount representing a total amount of money.

Return the fewest number of coins that you need to make up that amount. If that amount of money cannot be made up by any combination of the coins, return -1.

You may assume that you have an infinite number of each kind of coin.

I have written 2 recursive solutions, 1 in Python and 1 in Javascript. For some reason, the one in Javascript doesn’t produce the correct values for the same input, while the Python one always do.

Would like to ask if anyone knows what could be the reason for the difference in output. I tried with the following test cases:

coins = [1,2,5], amount = 11 => Expected: 3 
coins = [1,2], amount = 2 => Expected: 1

Here's the code I've written in the respective languages.

Javascript

var coinChange = function(coins, amount) {
    coins = coins.sort((a,b) => b -a )
    ans = helper(coins, amount, 0)
    if (ans >= Number.MAX_VALUE) {
        return -1
    }
    return ans;
};


function helper(coins, amount, pos) {
    if (pos >= coins.length || amount < 0) {
        return Number.MAX_VALUE; 
    } else if (amount === 0) {
        return 0; 
    }

    left = helper(coins, amount - coins[pos], pos) + 1
    right = helper(coins, amount, pos + 1)

    return Math.min(left, right)
}   

Using the above 2 test cases, it gets both test cases wrong.

coins = [1,2,5], amount = 11 => Expected: 3, gets 2
coins = [1,2], amount = 2 => Expected: 1, gets 2

Python

def coinChange(coins, amount):
    coins = sorted(coins, reverse = True)    
    ans = helper(coins, amount, 0)
    if (ans >= float("inf")):
        return -1
    return ans

def helper(coins, amount, pos):
    if (pos >= len(coins) or amount < 0):
        return float("inf")
    elif (amount == 0):
        return 0
    left = helper(coins, amount - coins[pos], pos) + 1
    right = helper(coins, amount, pos + 1)

    return min(left, right)

Using the above 2 test cases, it gets both tests correct.

coins = [1,2,5], amount = 11 => Expected: 3, gets 3
coins = [1,2], amount = 2 => Expected: 1, gets 1