The Wedding Juicer  (juicer.X)

Farmer Ran's cows have taken a side job creating interesting
punch-bowl designs as follows:

  * A flat board of size W cm x H cm is procured (3 <= W <= 300, 3
    <= H <= 300)

  * On every 1 cm x 1 cm square of the board, a 1 cm x 1 cm block
    is placed.  This block has some integer height B (1 <= B <=
    1,000,000,000)

The blocks are all glued together carefully so that punch will not
drain through them. They are glued so well, in fact, that the corner
blocks really don't matter!

FJ's cows can never figure out, however, just how much punch their
bowl designs will hold. Presuming the bowl is freestanding (i.e.,
no special walls around the bowl), calculate how much juice the
bowl can hold.  Some juice bowls, of course, leak out all the juice
on the edges and will hold 0.

PROBLEM NAME: juicer

INPUT FORMAT:

* Line 1: Two space-separated integers: W and H

* Lines 2..H+1: Line i+1 contains row i of bowl heights: W
        space-separated integers each of which represents the height B
        of a square in the bowl. The first integer is the height of
        column 1, the second integer is the height of column 2, and so
        on.

SAMPLE INPUT:

4 5
5 8 7 7
5 2 1 5
7 1 7 1
8 9 6 9
9 8 9 9

OUTPUT FORMAT:

* Line 1: A single integer that is the number of cc's the described
        bowl will hold.

SAMPLE OUTPUT:

12

OUTPUT DETAILS:

Fill-up the two squares of height 1 to height 5, for 4 cc for each square.
Fill the square of height 2 to height 5, for 3 cc of juice.  Fill the
square of height 6 to height 7 for 1 cc of juice.  2*4 + 3 + 1 = 12.