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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include<iostream>
#include<vector>
using namespace std;



int main()
{
	int H, W, N;
	int tem[101];
	vector <int> a;
	cin >> H>> W;
	cin >> N;
	int i,temp;
	for (i = 0; i < N; ++i)
	{
		cin >> temp;
		a.push_back(temp);
	}
	
	int tH=1;
	int point=1;

	while (tH<=H)
	{
		if (tH % 2 == 1)
			for (i = 1; i <= W; ++i)
			{
				tem[i] = point;
				--a[point - 1];
				if (a[point - 1] == 0)
					++point;
			}
		else
			for (i = W; i >= 1; --i)
			{
				tem[i] = point;
				--a[point - 1];
				if (a[point - 1] == 0)
					++point;
			}
		++tH;
		for (i = 0; i < W; ++i)
		{
			cout << tem[i+1];
			if (i < W - 1)
				cout << " ";
		}
		cout << endl;
	}


    return 0;
}