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 PHP7 (7.0.15) (judge verdict: Accepted)

<?php


fscanf(STDIN, "%d %d", $H, $W);
fscanf(STDIN, "%d", $N);
$a = explode(" ", trim(fgets(STDIN)));
array_unshift($a, 0);

$x = 0;
$y = 0;
$dx = 1;
$dy = 0;
$ans = array(array());
$cursor = 1;

while(true) {
    $a[$cursor]--;
    $color = $cursor;
    if ($a[$cursor] == 0) {
        $cursor++;
    }
    $ans[$x][$y] = $color;
    if ($cursor > $N) {
        break;
    }
    $x += $dx;
    $y += $dy;
    if ($x == $W) {
        $x--;
        $y++;
        $dx = 0;
        $dy = 1;
    }
    if ($y == $H) {
        $y--;
        $x--;
        $dx = -1;
        $dy = 0;
    }
    if ($x < 0) {
        $x++;
        $y--;
        $dx = 0;
        $dy = -1;
    }
    if ($y < 0) {
        $x++;
        $y++;
        $dx = 1;
        $dy = 0;
    }
    if (isset($ans[$x][$y])) {
        if ($dx == 1 && $dy == 0) {
            $x--;
            $y++;
            $dx = 0;
            $dy = 1;
        } elseif ($dx == -1 && $dy == 0) {
            $x++;
            $y--;
            $dx = 0;
            $dy = -1;
        } elseif ($dx == 0 && $dy == 1) {
            $y--;
            $x--;
            $dx = -1;
            $dy = 0;
        } elseif ($dx == 0 && $dy == -1) {
            $x++;
            $y++;
            $dx = 1;
            $dy = 0;
        }
    }
}

for ($y = 0; $y < $H; $y++) {
    $arrTmp = array();
    for ($x = 0; $x < $W; $x++) {
        $arrTmp[] = $ans[$x][$y];
    }
    echo implode(" ", $arrTmp) . PHP_EOL;
}