F. Astronomy
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

It is known that any star cannot be simultaneously visible both from the south pole and from the north pole. Using this, the Penguin and the Bear decided to count all the stars in space. They stood at the poles at the same time, and each counted the stars that are visible to him. You know these two numbers. Using these data, answer the question: how many stars are there in space?

Input

The two input lines contain the numbers $$$A$$$ and $$$B$$$ $$$(1 \leq A,B \lt 10^{10^5})$$$ - the number of stars counted by the Penguin and the Bear. These integers don't contain leading zeros.

Output

Output one number - the answer to the problem. This number must not contain leading zeros.

Example
Input
705
33
Output
738