| English | 简体中文 |

# 860. Lemonade Change

## Description

At a lemonade stand, each lemonade costs `$5`

. Customers are standing in a queue to buy from you and order one at a time (in the order specified by bills). Each customer will only buy one lemonade and pay with either a `$5`

, `$10`

, or `$20`

bill. You must provide the correct change to each customer so that the net transaction is that the customer pays `$5`

.

Note that you do not have any change in hand at first.

Given an integer array `bills`

where `bills[i]`

is the bill the `i`

customer pays, return ^{th}`true`

*if you can provide every customer with the correct change, or* `false`

*otherwise*.

**Example 1:**

Input:bills = [5,5,5,10,20]Output:trueExplanation:From the first 3 customers, we collect three $5 bills in order. From the fourth customer, we collect a $10 bill and give back a $5. From the fifth customer, we give a $10 bill and a $5 bill. Since all customers got correct change, we output true.

**Example 2:**

Input:bills = [5,5,10,10,20]Output:falseExplanation:From the first two customers in order, we collect two $5 bills. For the next two customers in order, we collect a $10 bill and give back a $5 bill. For the last customer, we can not give the change of $15 back because we only have two $10 bills. Since not every customer received the correct change, the answer is false.

**Constraints:**

`1 <= bills.length <= 10`

^{5}`bills[i]`

is either`5`

,`10`

, or`20`

.