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

Constraints

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

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).

Examples

Input

5 10 2

Output

3

Input

6 20 7

Output

2

Input

1 100 1

Output

100

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