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.

Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ACM-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

D. Polycarp's Picture Gallery

time limit per test

2 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputPolycarp loves not only to take pictures, but also to show his photos to friends. On his personal website he has recently installed a widget that can display *n* photos with the scroll option. At each moment of time the widget displays exactly one photograph with the option showing the previous/next one. From the first photo, you can switch to the second one or to the *n*-th one, from the second photo you can switch to the third one or to the first one, etc. Thus, navigation is performed in a cycle.

Polycarp's collection consists of *m* photo albums, the *i*-th album contains *a*_{i} photos. Polycarp wants to choose *n* photos and put them on a new widget. To make watching the photos interesting to the visitors, he is going to post pictures so that no two photos from one album were neighboring (each photo will have exactly two neighbors, the first photo's neighbors are the second and the *n*-th one).

Help Polycarp compile a photo gallery. Select *n* photos from his collection and put them in such order that no two photos from one album went one after the other.

Input

The first line contains two integers *n* and *m* (3 ≤ *n* ≤ 1000, 1 ≤ *m* ≤ 40), where *n* is the number of photos on the widget, and *m* is the number of albums. The second line contains *m* integers *a*_{1}, *a*_{2}, ..., *a*_{m} (1 ≤ *a*_{i} ≤ 1000), where *a*_{i} is the number of photos in the *i*-th album.

Output

Print the single number -1 if there is no solution. Otherwise, print *n* numbers *t*_{1}, *t*_{2}, ..., *t*_{n}, where *t*_{i} represents the number of the album of the *i*-th picture in the widget. The albums are numbered from 1 in the order of their appearance in the input. If there are several solutions, print any of them.

Examples

Input

4 3

1 3 5

Output

3 1 3 2

Input

10 2

5 5

Output

2 1 2 1 2 1 2 1 2 1

Input

10 3

1 10 3

Output

-1

Codeforces (c) Copyright 2010-2017 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Mar/25/2017 16:34:31 (c2).

Desktop version, switch to mobile version.
User lists

Name |
---|