103020: [Atcoder]ABC302 A - Attack

Problem Statement

There is an enemy with stamina $A$. Every time you attack the enemy, its stamina reduces by $B$.

At least how many times do you need to attack the enemy to make its stamina $0$ or less?

Constraints

• $1 \le A,B \le 10^{18}$
• $A$ and $B$ are integers.

Input

The input is given from Standard Input in the following format:

$A$ $B$

Output

Print the answer.

Sample Input 1

7 3

Sample Output 1

3

Attacking three times make the enemy's stamina $-2$.

Attacking only twice makes the stamina $1$, so you need to attack it three times.

Sample Input 2

123456789123456789 987654321

Sample Output 2

124999999

Sample Input 3

999999999999999998 2

Sample Output 3

499999999999999999

问题描述

有一个敌人，体力为$A$。每次你攻击敌人，它的体力减少$B$。

至少需要攻击敌人多少次，才能使它的体力为0或更少？

限制条件

• $1 \le A,B \le 10^{18}$
• $A$和$B$都是整数。

输入

输入从标准输入以以下格式给出：

$A$ $B$

输出

输出答案。

样例输入1

7 3

样例输出1

3

攻击三次会使敌人的体力变为-2。

攻击两次只能使体力变为1，因此需要攻击三次。

样例输入2

123456789123456789 987654321

样例输出2

124999999

样例输入3

999999999999999998 2

样例输出3

499999999999999999