Competitions

# October 7 - BMTK Programming School, High League

# Simple Addition

Let's define the next recursive function **F**(**n**), where

Let's define the function **S** (**p**, **q**) as follows:

In this problem you have to calculate **S** (**p**, **q**) on given values of **p** and **q**.

#### Input

Consists of multiple test cases. Each line contains two nonnegative integers **p** and **q** (**p** ≤ **q**), separated by space. **p** and **q** will fit in **32** bit signed integer. Input is terminated by a line with two negative integers. This line should not be processed.

#### Output

For each pair **p** and **q** print the value **S** (**p**, **q**) on a single line.

Input example #1

1 10 10 20 30 40 -1 -1

Output example #1

46 48 52