The hostess leaves Tom a message. However, Jerry plays a trick. He secretly deletes one character of the message, and totally changes the meaning. Please find the character which Jerry deletes.

There are multiple cases. The number of cases will be no more than 50. 

      Each case contains two lines. The first line is the hostess’s message, and the second line is the message after Jerry makes a change.

      All messages only contain lowercase letters, and each of their length doesn’t exceed 1000.

For each case, print the character which Jerry deletes.