You are given two binary strings a and b of the same length. You can perform the following two operations on the string a:
Find the minimum cost to make the string a equal to b. It is not allowed to modify string b
Input:
The first line contains a single integer n
(1≤n≤10^6) — the length of the strings a and b
The second and third lines contain strings a and b respectively.
Both strings a and b have length n and contain only '0' and '1'.
Output:
Output the minimum cost to make the string a equal to b.