Sum Positive Values Until Zero

Source: Phước Hưng OJ

Version: Phuoc Hung OJ Extended

Problem Statement

Read nonnegative integers until the first zero. Compute the sum of positive numbers before the zero; an immediate zero gives zero.

Input

Whitespace-separated nonnegative integers terminated by their first zero.

Output

Print the sum of the values before zero.

Subtasks

• Subtask 1 (20%): At most 5 values, each 1..10.
• Subtask 2 (30%): At most 200 values, each 1..10000.
• Subtask 3 (50%): At most 100000 values, each 1..1000000.

Examples

Example 1

Input

3 5 0

Output

8

Explanation

The two positive numbers add to 8; zero terminates input.

Example 2

Input

0

Output

0

Explanation

There are no values before the zero.