Yaroslav thinks that two strings *s* and *w*, consisting of digits and having length *n* are non-comparable if there are two numbers, *i* and *j* (1 ≤ *i*, *j* ≤ *n*), such that *s*<sub class="lower-index">*i*</sub> &gt; *w*<sub class="lower-index">*i*</sub> and *s*<sub class="lower-index">*j*</sub> &lt; *w*<sub class="lower-index">*j*</sub>. Here sign *s*<sub class="lower-index">*i*</sub> represents the *i*-th digit of string *s*, similarly, *w*<sub class="lower-index">*j*</sub> represents the *j*-th digit of string *w*.

A string's template is a string that consists of digits and question marks ("?").

Yaroslav has two string templates, each of them has length *n*. Yaroslav wants to count the number of ways to replace all question marks by some integers in both templates, so as to make the resulting strings incomparable. Note that the obtained strings can contain leading zeroes and that distinct question marks can be replaced by distinct or the same integers.

Help Yaroslav, calculate the remainder after dividing the described number of ways by 1000000007 (10<sup class="upper-index">9</sup> + 7).
The first line contains integer *n* (1 ≤ *n* ≤ 10<sup class="upper-index">5</sup>) — the length of both templates. The second line contains the first template — a string that consists of digits and characters "?". The string's length equals *n*. The third line contains the second template in the same format.
# not E i, j((si > wi) and (sj < wj))
# forall i, j not(si > wi) or not (sj < wj)
# forall i,j (si <= wi or sj >= wj)

n = int(input())

s = list(input())
w = list(input())

contS = s.count("?")
contW = w.count("?")

total = 10 ** (contS + contW)

maiorIgual = 1
menorIgual = 1
igual = 1
for i in range(0, n):

	if (s[i] == '?'):

		if (w[i] == '?'):
			maiorIgual *= 55
			menorIgual *= 55
			igual *= 10

		else:
			maiorIgual *= 10 - int(w[i])
			menorIgual *= int(w[i]) + 1
			igual *= 1

	else:

		if (w[i] == '?'):
			maiorIgual = 10 - int(s[i])
			menorIgual = int(s[i]) + 1
			igual *= 1

		else: 

			if (s[i] > w[i]):
				maiorIgual *= 1
				menorIgual *= 0
				igual *= 0

			if (s[i] == w[i]):
				igual *= 1
				maiorIgual *= 1
				menorIgual *= 1

			if (s[i] < w[i]):
				maiorIgual *= 0
				menorIgual *= 1	
				igual *= 0

print((total - menorIgual - maiorIgual + igual) % 1000000007)


