evenodd.py

from itertools import product

def Perm(num):
    return sum([int(i) for i in num])

first, second = map(int, input().split())

rep = int(input())

arr = [str(i) for i in range(first, second + 1)]

total_count = 0

for i in product(arr, repeat=rep):
    if Perm(i) % 2 == 0:
        total_count += 1

print(total_count % 1000000007)