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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;

class Progaram
{
    static Int32 H;
    static Int32 W;
    static Int32 N;

    static void Main(string[] args)
    {
        var l = Console.ReadLine().Split(' ').Select(x => Int32.Parse(x)).ToArray();
        H = l[0];
        W = l[1];
        N = Int32.Parse(Console.ReadLine());
        var line = Console.ReadLine().Split(' ').Select(x => Int32.Parse(x)).ToArray();
        var retu1 = new List<Int32>();
        for (var i = 0; line.Length > i; i++)
        {
            for (var j = 0; line[i] > j; j++)
            {
                retu1.Add(i + 1);
            }
        }

        var table = new Int32[H][];
        for (var i = 0; H > i; i++)
        {
            var tas = new Int32[W];
            for (var j = 0; W > j; j++)
            {
                tas[j] = retu1[0];
                retu1.RemoveAt(0);
            }
            if (i % 2 == 1)
            {
                Array.Reverse(tas);
            }
            table[i] = tas;
        }
     
        for (var i = 0; H > i; i++)
        {
            for (var j = 0; W > j; j++)
            {
                Console.Write(table[i][j]);
                Console.Write(' ');
            }
            Console.WriteLine();
        }
    }
}