def main():

    left, right, div = [int(x) for x in input().split()]

    ans = sum(x % div == 0 for x in range(left, right + 1))

    print(ans)





if __name__ == '__main__':

    main()

def main():

    left, right, div = [int(x) for x in input().split()]

    ans = right // div - (left - 1) // div

    print(ans)





if __name__ == '__main__':

    main()

def main():
    left, right, div = [int(x) for x in input().split()]
    ans = sum(x % div == 0 for x in range(left, right + 1))
    print(ans)


if __name__ == "__main__":
    main()

def main():
    left, right, div = [int(x) for x in input().split()]
    ans = right // div - (left - 1) // div
    print(ans)


if __name__ == "__main__":
    main()

-    ans = sum(x % div == 0 for x in range(left, right + 1)) +    ans = right // div - (left - 1) // div