For his English FSE, Adam decided to take some characters, cut them up, and put them into a bag. Because he is so good at English, his English teacher is guaranteed to give him a 100‰ - but only if his deep references are on point. Unfortunately, while piling in the characters, Adam messed up and accidentally put in an extra character. Can you help him find out what the extra character is?

Input Specification

On the first line, a string of characters denoting the letters Adam put into his bag.
On the second line, a string of characters denoting the letters in the bag.
The length of both these strings will be less than or equal to ~5 \times 10^6 + 1~.

Output Specification

The extra letter, on one line.

Sample Input 1

wqhdippcr
rcipdphw

Sample Output 1

q

Sample Input 2

utyxbGrdqh[
yt[ubxhGdq

Sample Output 2

r