A+B until two zeros

Write a program that reads two integers $A$ and $B$ and prints $A+B$.

The input holds several test cases. Each test case is one line, and that line gives $A$ and $B$ separated by a space. ($0 < A, B < 10$)

The last line of the input gives two zeros. That line marks the end of the input and is not a test case. The input may consist of that line alone.

For each test case, print $A+B$ on its own line, in the order the test cases were given. If there is no test case, print nothing.