ds-algo-study
Version:
Just experimenting with publishing a package
44 lines (31 loc) • 990 B
JavaScript
/*
You are given coins of different denominations and a total amount of money. Write a function to compute the number of combinations that make up that amount. You may assume that you have infinite number of each kind of coin.
Example 1:
Input: amount = 5, coins = [1, 2, 5]
Output: 4
Explanation: there are four ways to make up the amount:
5=5
5=2+2+1
5=2+1+1+1
5=1+1+1+1+1
Example 2:
Input: amount = 3, coins = [2]
Output: 0
Explanation: the amount of 3 cannot be made up just with coins of 2.
Example 3:
Input: amount = 10, coins = [10]
Output: 1
*/
let change = function (amount, coins, memo={}) {
let key = amount + '-' + coins;
if (key in memo) return memo[key];
if (amount === 0) return 1;
let currentCoin = coins[coins.length - 1]
let total = 0;
for (let qty = 0; qty * currentCoin <= amount; qty++) {
total += change(amount - qty * currentCoin, coins.slice(0, -1), memo);
}
memo[key] = total;
return memo[key]
};
console.log(change(5, [1, 2, 5]))