## Problem Description

There are two binary strings, you task is to change one into another. The only operation you can do is reversing some continual bits of a binary string. For example, after conversing the first four bits of "10101", you change it into "01011".

## Input

The first line is an interger T, means the number of test cases. Follows T lines, each line contain two binary strings a and b (they are not longer than 20 bits), you should change a into b.

## Output

Output the minimal number you have done to change one into another. You can assume that it always have a solution.

## Sample Input

2
1001 0110
10101 01011

## Sample Output

2
1

## Source

FZU 2006 ICPC Qualification Round I