Three-Case Fallthrough

Source: Phước Hưng OJ

Version: Phuoc Hung OJ Extended

Problem Statement

Start with s = 0 and execute switch(k): case 1 adds 1, case 2 adds 2, and case 3 adds 3 then breaks. There is deliberately no break after cases 1 and 2; default sets s = 0. Print the final s.

Input

One integer k.

Output

Print the final s.

Subtasks

• Subtask 1 (20%): 1 <= k <= 2.
• Subtask 2 (30%): 1 <= k <= 3.
• Subtask 3 (50%): -10^9 <= k <= 10^9.

Examples

Example 1

Input

1

Output

6

Explanation

Starting in case 1 adds 1, then 2, then 3, giving 6.

Example 2

Input

2

Output

5

Explanation

Starting in case 2 adds 2 and 3 only, giving 5.