#!/usr/bin/env python3

# atcoder 

# Türkler var mı?

# Herkese memnün oldum

import sys



iimr = lambda: map(int, sys.stdin.readline().rstrip().split())

readline = sys.stdin.buffer.readline

sys.setrecursionlimit(10 ** 8)

MOD = (10 ** 9) + 7  # operować sobie na typie int32_t





def 関数(l,r,d):

    res = 0

    for i in range(l, r+1):

        if i % d == 0:

            res += 1

    return res



def çözmek():

    L, R, d = iimr()

    res = []

    res.append(関数(L, R, d))

    print(*res, sep="\n")



if __name__ == "__main__":

    çözmek()

#!/usr/bin/env python3

# atcoder 

# Türkler var mı?

# Herkese memnün oldum

import sys



iimr = lambda: map(int, sys.stdin.readline().rstrip().split())

readline = sys.stdin.buffer.readline

sys.setrecursionlimit(10 ** 8)

MOD = (10 ** 9) + 7  # operować sobie na typie int32_t





def 関数(l,r,d):

    res = 0

    for i in range(l, r+1):

        res += i % d == 0

    return res



def çözmek():

    L, R, d = iimr()

    res = []

    res.append(関数(L, R, d))

    print(*res, sep="\n")



if __name__ == "__main__":

    çözmek()

#!/usr/bin/env python3
# atcoder
# Türkler var mı?
# Herkese memnün oldum
import sys

iimr = lambda: map(int, sys.stdin.readline().rstrip().split())
readline = sys.stdin.buffer.readline
sys.setrecursionlimit(10**8)
MOD = (10**9) + 7  # operować sobie na typie int32_t


def 関数(l, r, d):
    res = 0
    for i in range(l, r + 1):
        if i % d == 0:
            res += 1
    return res


def çözmek():
    L, R, d = iimr()
    res = []
    res.append(関数(L, R, d))
    print(*res, sep="\n")


if __name__ == "__main__":
    çözmek()

#!/usr/bin/env python3
# atcoder
# Türkler var mı?
# Herkese memnün oldum
import sys

iimr = lambda: map(int, sys.stdin.readline().rstrip().split())
readline = sys.stdin.buffer.readline
sys.setrecursionlimit(10**8)
MOD = (10**9) + 7  # operować sobie na typie int32_t


def 関数(l, r, d):
    res = 0
    for i in range(l, r + 1):
        res += i % d == 0
    return res


def çözmek():
    L, R, d = iimr()
    res = []
    res.append(関数(L, R, d))
    print(*res, sep="\n")


if __name__ == "__main__":
    çözmek()

-        if i % d == 0: -            res += 1 +        res += i % d == 0