A Different Problem

Write a program that computes the difference between non-negative integers.

Input

The input consists of multiple test cases (at least $1$ and at most $40$), one per line. Each test case consists of a pair of integers, between $0$ and $10^{15}$ (inclusive). The input is terminated by end of file.

Output

For each pair of integers in the input, output one line, containing the absolute value of their difference.

Sample Input 1 Sample Output 1
10 12
71293781758123 72784
1 12345677654321
2
71293781685339
12345677654320