URI Online Judge | 1149

Summing Consecutive Integers

Adapted by Neilor Tonin, URI Brazil

Timelimit: 1

Write an algorithm to read a value A and a value N. Print the sum of N numbers from A (inclusive). While N is negative or ZERO, a new N (only N) must be read. All input values are in the same line.

Input

The input contains only integer values, ​​can be positive or negative.

Output

The output contains only an integer value.

Input Sample Output Sample

3 2

7

3 -1 0 -2 2

7