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 Haskell (GHC 7.10.3) (judge verdict: Accepted)

import Control.Applicative( (<$>))
import Data.List( sortBy)
import Data.Function( on)
import Control.Monad( forM_)

data Direction = LEFT | RIGHT | UP | DOWN

main = do
    let
	readLine = map read . words <$> getLine
    [h_, w_] <- readLine
    _n_ <- readLn::IO Int
    as_ <- readLine
    let
	uzu 0 _ _ _ _ _ _ = []
	uzu n l u b r RIGHT p@(i,j)
	  | j<r		= p:(uzu (n-1) l u b r RIGHT (i,j+1))
	  | otherwise	= p:(uzu (n-1) l u b (r-1) DOWN (i+1,j))
	uzu n l u b r DOWN p@(i,j)
	  | i<b		= p:(uzu (n-1) l u b r DOWN (i+1,j))
	  | otherwise	= p:(uzu (n-1) l u (b-1) r LEFT (i,j-1))
	uzu n l u b r LEFT p@(i,j)
	  | l<j		= p:(uzu (n-1) l u b r LEFT (i,j-1))
	  | otherwise	= p:(uzu (n-1) (l+1) u b r UP (i-1,j))
	uzu n l u b r UP p@(i,j)
	  | u<i		= p:(uzu (n-1) l u b r UP (i-1,j))
	  | otherwise	= p:(uzu (n-1) l (u+1) b r RIGHT (i,j+1))

	poss = uzu (h_*w_) 1 2 h_ w_ RIGHT (1,1)
	
	gridDataList
	  = let
		decode _ [] = []
		decode n (a:as) = replicate a n:(decode (n+1) as)
		as' = concat $ decode 1 as_
		list = zip poss as'
	    in
		sortBy (compare `on` fst) list

	
	printGrid lines
	  = forM_ lines $ \line ->
		do
		forM_ line $	\v -> putStr $ (show v) ++ " "
		putStrLn ""
	
	chops _ [] = []
	chops n list
	  = let
		(sausage, rest) = splitAt n list
	    in
		sausage:(chops n rest)

    printGrid . chops w_ $ snd <$> gridDataList