leetcode2806. Round up the account balance after purchase

• easy : https://leetcode.cn/problems/account-balance-after-rounded-purchase/

• To start, you have $100 in your bank account.

• You are given an integer purchaseAmount that represents the amount you are willing to spend on a purchase.

• In a store, when you make a purchase, the actual amount spent will be rounded up to the nearest multiple of 10. In other words, you will actually pay a non-negative amount roundedAmount such that roundedAmount is a multiple of 10 and abs(roundedAmount - purchaseAmount) is the smallest value.

• If there is more than one multiple to the nearest 10, the larger multiple is your actual payout amount.

• Please return an integer, which represents the remaining balance after the purchase under the premise that you are willing to spend an amount of purchaseAmount.

• Note: 0 is also a multiple of 10.

示例 1：

输入：purchaseAmount = 9
输出：90
解释：这个例子中，最接近 9 的 10 的倍数是 10 。所以你的账户余额为 100 - 10 = 90 。
示例 2：

输入：purchaseAmount = 15
输出：80
解释：这个例子中，有 2 个最接近 15 的 10 的倍数：10 和 20，较大的数 20 是你的实际开销。
所以你的账户余额为 100 - 20 = 80 。
 

提示：

0 <= purchaseAmount <= 100

code

class Solution {
    
    
public:
    int accountBalanceAfterPurchase(int purchaseAmount) {
    
    
        int roundedAmount =0;
        if (purchaseAmount % 10 >= 5){
    
    
            roundedAmount = 10;
        }

        return 100 - (purchaseAmount/10)*10 - roundedAmount ;
    }
};