You are given nonnegative integers a and b (a ≤ b), and a positive integer x. Among the integers between a and b, inclusive, how many are divisible by x?
a, b, x = map(int, input().split())
def f(n, x):
    if n == -1:
        return 0
    return n/x + 1
print(f(b, x) - f(a-1, x))
a, b, x = map(int, input().split())
def f(n, x):
    if n == -1:
        return 0
    return n//x + 1
print(f(b, x) - f(a-1, x))