You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
49 lines
1.5 KiB
49 lines
1.5 KiB
/**
|
|
* File: coin_change_greedy.js
|
|
* Created Time: 2023-09-02
|
|
* Author: Justin (xiefahit@gmail.com)
|
|
*/
|
|
|
|
/* 零錢兌換：貪婪 */
|
|
function coinChangeGreedy(coins, amt) {
|
|
// 假設 coins 陣列有序
|
|
let i = coins.length - 1;
|
|
let count = 0;
|
|
// 迴圈進行貪婪選擇，直到無剩餘金額
|
|
while (amt > 0) {
|
|
// 找到小於且最接近剩餘金額的硬幣
|
|
while (i > 0 && coins[i] > amt) {
|
|
i--;
|
|
}
|
|
// 選擇 coins[i]
|
|
amt -= coins[i];
|
|
count++;
|
|
}
|
|
// 若未找到可行方案，則返回 -1
|
|
return amt === 0 ? count : -1;
|
|
}
|
|
|
|
/* Driver Code */
|
|
// 貪婪：能夠保證找到全域性最優解
|
|
let coins = [1, 5, 10, 20, 50, 100];
|
|
let amt = 186;
|
|
let res = coinChangeGreedy(coins, amt);
|
|
console.log(`\ncoins = ${coins}, amt = ${amt}`);
|
|
console.log(`湊到 ${amt} 所需的最少硬幣數量為 ${res}`);
|
|
|
|
// 貪婪：無法保證找到全域性最優解
|
|
coins = [1, 20, 50];
|
|
amt = 60;
|
|
res = coinChangeGreedy(coins, amt);
|
|
console.log(`\ncoins = ${coins}, amt = ${amt}`);
|
|
console.log(`湊到 ${amt} 所需的最少硬幣數量為 ${res}`);
|
|
console.log('實際上需要的最少數量為 3 ，即 20 + 20 + 20');
|
|
|
|
// 貪婪：無法保證找到全域性最優解
|
|
coins = [1, 49, 50];
|
|
amt = 98;
|
|
res = coinChangeGreedy(coins, amt);
|
|
console.log(`\ncoins = ${coins}, amt = ${amt}`);
|
|
console.log(`湊到 ${amt} 所需的最少硬幣數量為 ${res}`);
|
|
console.log('實際上需要的最少數量為 2 ，即 49 + 49');
|