Directi Q1

You are given two strings, say A and B, of the same length, say N. You can swap A[i] and B[i] for all i between 1 and N, inclusive. You cannot swap two characters within A, or within B. Also, you can only swap a character in A with the character at the same index in B, and with no other character. You can perform this operation zero or more times.
You wish to modify the strings through the operations in such a way that the number of unique characters in the strings is small. In fact if n(A) is the number of unique characters in A and n(B) is the number of unique characters in B; you wish to perform the operations such that max(n(A),n(B)) is as small as possible.
Print the value of max(n(A),n(B)) after all the operations.
Sample Input

3
7
directi
itcerid
5
ababa
babab
5
abaaa
baabb

Sample Output

4
1
2
Explanation

In the first test case, initially max(n(directi),n(itcerid)) = 6. You can modify the two strings such that they are "iirerii" and "dtcectd". String A has 3 unique characters and String B has 4 unique characters. Hence answer is 4. You cannot do better.