Problem:
Score : 400 points

Problem Statement

We have a grid with H rows and W columns of squares.
Snuke is painting these squares in colors 1, 2, ..., N.
Here, the following conditions should be satisfied:

For each i (1 ≤ i ≤ N), there are exactly a_i squares painted in Color i. Here, a_1 + a_2 + ... + a_N = H W.

For each i (1 ≤ i ≤ N), the squares painted in Color i are 4-connected. That is, every square painted in Color i can be reached from every square painted in Color i by repeatedly traveling to a horizontally or vertically adjacent square painted in Color i.

Find a way to paint the squares so that the conditions are satisfied.
It can be shown that a solution always exists.

Constraints

1 ≤ H, W ≤ 100

1 ≤ N ≤ H W

a_i ≥ 1

a_1 + a_2 + ... + a_N = H W

Input

Input is given from Standard Input in the following format:

H W
N
a_1 a_2 ... a_N

Output

Print one way to paint the squares that satisfies the conditions.
Output in the following format:

c_{1 1} ... c_{1 W}
:
c_{H 1} ... c_{H W}

Here, c_{i j} is the color of the square at the i-th row from the top and j-th column from the left.

Sample Input 1

2 2
3
2 1 1

Sample Output 1

1 1
2 3

Below is an example of an invalid solution:

1 2
3 1

This is because the squares painted in Color 1 are not 4-connected.

Sample Input 2

3 5
5
1 2 3 4 5

Sample Output 2

1 4 4 4 3
2 5 4 5 3
2 5 5 5 3

Sample Input 3

1 1
1
1

Sample Output 3

1

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.*;

class Main
{
	public static void main(String[] args) 
	{
		Scanner sc = new Scanner(System.in);
		
		int n = sc.nextInt(),
			m = sc.nextInt(),
			colors = sc.nextInt();
		int color_num[] = new int[colors];
		
		int arr[][] = new int[n][m];

		for(int i = 0; i < colors; i++)
			color_num[i] = sc.nextInt();

		int i = 0, j = 0, addY = 1; 
		
		for(int now_color = 0; now_color < colors; now_color++)
		{
			for(int color_cnt = 0; color_cnt < color_num[now_color]; j += addY, color_cnt++)
			{
				if(j < 0)
				{
					addY = 1;
					j = 0;
					i++;
				}
				else if(j >= m)
				{
					addY = -1;
					j = m - 1;
					i++;
				}
				arr[i][j] = (now_color + 1);
			}
		}

		for(i = 0; i < n; i++)
		{
			for(j = 0; j < m; j++)
				System.out.print(arr[i][j] + " ");
			System.out.println();
		}
		
	}
}