Description:

Calculate a + b

Input:

The input will be consist of a series of pairs of integers a and b,separated by a space, one pair of integers per line, 0 0 means the end of the input, and do not need to output.

Output:

For each pair of input integers a and b you should output the sum of a and b in one line,and with one line of output for each line in input.

Sample Input:

1 5
0 0

Sample Output:

6