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1886E · I Wanna be the Team Leader

2400 · bitmasks, constructive algorithms, dp

Problem: Monocarp is a team leader in a massive IT company.

There are mm projects his team of programmers has to complete, numbered from 11 to mm. The ii-th project has a difficulty level bib_i.

There are nn programmers in the team, numbered from 11 to nn. The jj-th programmer has a stress tolerance level aja_j.

Monocarp wants to assign the programmers to the projects in such a way that:

  • each programmer is assigned to no more than one project;
  • each project has at least one programmer assigned to it;
  • let kk programmers be assigned to the ii-th project; then all the assigned programmers have to have a stress tolerance level greater than or equal to bik\frac{b_i}{k}.

Help Monocarp to find a valid assignment. If there are multiple answers, print any of them.

Input Format: The first line contains two integers nn and mm (1n21051 \le n \le 2 \cdot 10^5; 1m201 \le m \le 20) — the number of programmers and the number of projects.

The second line contains nn integers a1,a2,,ana_1, a_2, \dots, a_n (1ai1091 \le a_i \le 10^9) — the stress tolerance level of each programmer.

The third line contains mm integers b1,b2,,bmb_1, b_2, \dots, b_m (1bi1091 \le b_i \le 10^9) — the difficulty level of each project.

Output Format: If there is no valid assignment, print "NO".

Otherwise, in the first line, print "YES". In the ii-th of the next mm lines, print the list of the programmers assigned to the ii-th project: first, the number of programmers, then their indices in an arbitrary order.

If there are multiple answers, print any of them.

Sample Cases

Case 1

Input

5 3
4 6 100 5 1
50 1 12

Output

YES
1 3
1 5
3 2 4 1

Case 2

Input

5 3
3 6 100 5 1
50 1 12

Output

NO

Case 3

Input

5 3
2 2 2 2 4
3 5 1

Output

YES
1 5
3 1 2 3
1 4

Case 4

Input

5 1
10 20 30 40 50
4

Output

YES
1 4

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