Problem Statement

How many multiples of d are there among the integers between L and R (inclusive)?

Input

Input is given from Standard Input in the following format:
L R d

Output

Print the number of multiples of d among the integers between L and R (inclusive).

Constraints

• All values in input are integers.
• $1 \leq L \leq R \leq 100$
• $1 \leq d \leq 100$

Sample Input 1

5 10 2

Sample Output 1

3

• Among the integers between 5 and 10, there are three multiples of 2: 6, 8, and 10.

Sample Input 2

6 20 7

Sample Output 2

2

• Among the integers between 6 and 20, there are two multiples of 7: 7 and 14.

Sample Input 3

1 100 1

Sample Output 3

100

见题面 Input 部分

见题面 Output 部分