Package for this problem was not updated by the problem writer or Codeforces administration after we’ve upgraded the judging servers. To adjust the time limit constraint, solution execution time will be multiplied by 2. For example, if your solution works for 400 ms on judging servers, then value 800 ms will be displayed and used to determine the verdict.

The following languages are additionally available for the problems from the contest

April Fools Day Contest:

- Secret_171

Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

No tag edit access

C. A Piece of Cake

time limit per test

2 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputHow to make a cake you'll never eat.

Ingredients.

- 2 carrots
- 0 calories
- 100 g chocolate spread
- 1 pack of flour
- 1 egg

Method.

- Put calories into the mixing bowl.
- Take carrots from refrigerator.
- Chop carrots.
- Take chocolate spread from refrigerator.
- Put chocolate spread into the mixing bowl.
- Combine pack of flour into the mixing bowl.
- Fold chocolate spread into the mixing bowl.
- Add chocolate spread into the mixing bowl.
- Put pack of flour into the mixing bowl.
- Add egg into the mixing bowl.
- Fold pack of flour into the mixing bowl.
- Chop carrots until choped.
- Pour contents of the mixing bowl into the baking dish.

Serves 1.

Input

The only line of input contains a sequence of integers *a*_{0}, *a*_{1}, ... (1 ≤ *a*_{0} ≤ 100, 0 ≤ *a*_{i} ≤ 1000 for *i* ≥ 1).

Output

Output a single integer.

Examples

Input

4 1 2 3 4

Output

30

Codeforces (c) Copyright 2010-2020 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Jan/29/2020 12:41:24 (e1).

Desktop version, switch to mobile version.

Supported by

User lists

Name |
---|